Define in Preclinical Systolic Dysfunction (PSD) With Renal Dysfunction, the Cardiorenal and Humoral Actions of Chronic Type V Phosphodiesterase (PDEV) Inhibition
Phase: PHASE1
Conditions: Cardiomyopathy, Renal Impairment
Sponsor: Mayo Clinic

 
 
Define in Preclinical Systolic 
Dysfunction (PSD) with renal 
dysfunction, the cardiorenal 
and humoral actions of chronic 
PDEV inhibition 
 
NCT01970176   
 
7/21/2016 

1 
 
Version4 – IRB Approved 7/21/2016 
 
Define in Preclinical Systolic Dysfunction (PSD) with renal dysfunction, the 
cardiorenal and humoral actions of chronic PDEV inhibition  
 
Principal Investigator: Horng H Chen MD, Professor of Medicine 
 
Co-Investigators: Paul Mckie MD, John A Schirger MD, John C Burnett Jr MD 
 
Study Co-ordinators: Sherry Benike RN and Lynn Harstad  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

2 
 
 
 
Summary 
Preclinical systolic dysfunction (PSD) is the initial compensated phase of left 
ventricular systolic dysfunction without symptoms of HF. 
We have previously demonstrated that a common hallmark of both preclinical 
systolic dysfunction (PSD) was impaired renal function, characterized by decreased 
glomerular filtration rate (GFR) and renal blood flow (RBF), with an attenuated plasma 
natriuretic peptide and renal cyclic guanosine 3’,5’-monophosphate (cGMP) response to 
saline volume expansion (VE).   The mechanism for the renal dysfunction and 
attenuated renal cGMP response to VE is undefined.  
 
Type V phosphodiesterase (PDEV) metabolizes cGMP and is abundant in the 
kidney, vasculature, and has been recently reported in the heart.(2,3)  We and others 
have demonstrated that renal PDEV is up-regulated in experimental HF and may lead to 
the attenuation of renal cGMP generation in response to both endogenous and 
exogenous BNP, thus serving as a mechanism for renal resistance to BNP. 
Furthermore, in experimental overt HF, 10 days of PDEV inhibition treatment resulted in 
reduction of left ventricular (LV) mass, increased LV fractional shortening and cardiac 
output.  Furthermore, chronic PDEV inhibition did enhance the renal actions of 
exogenous BNP, specifically improving GFR and renal cGMP generation.(4)  PDEV 
inhibitors are FDA approved for erectile dysfunction and pulmonary hypertension. 
 
Objective: To determine the effect of 12 weeks of chronic PDEV inhibition with 
Tadalafil  versus placebo  on basal cardiorenal and humoral function and on the 
integrated cardiorenal and humoral response to acute sodium loading in subjects 
with PSD and renal dysfunction.  
 
Hypotheses:  
1. Chronic PDEV inhibition with Tadalafil will result in the improvement of 
renal function measured by glomerular filtration rate (GFR) as compared 
to placebo in subjects with PSD and renal dysfunction. 
2. Chronic PDEV inhibition with Tadalafil will result in the improvement 
urinary sodium excretion and urinary cGMP excretion in response to acute 
sodium loading as compared to placebo in subjects with PSD and renal 
dysfunction. 
 
Study design:  
This will be a single center double blind placebo-controlled design. Subjects 
will be randomized in a 2:1 design, to the Tadalafil alone group  or placebo .  
 
Primary end points: 
1. Change in GFR from baseline after 12 weeks of chronic Tadalafil versus 
placebo. 
2. Change in urinary sodium excretion and urinary cGMP excretion in 
response to acute sodium loading from baseline after 12 weeks of chronic 
Tadalafil versus placebo. 
 
 

3 
 
 
Background 
In the AHA/ACC classification of HF, stage B is defined as patients with 
abnormal heart structure/function (systolic or diastolic dysfunction) without symptoms. 
This concept of preclinical HF is based on the fact that abnormal heart structure/function 
can be detected by complementary methods before the development of symptoms.(5,8) 
Patients with those abnormalities may progress to heart failure and are at increased risk 
of adverse cardiac events.  Preclinical systolic dysfunction (PSD) is the initial 
compensated phase of left ventricular systolic dysfunction without symptoms of HF. 
We have previously demonstrated that a common hallmark of both preclinical 
systolic dysfunction (PSD) was impaired renal function, characterized by decreased 
glomerular filtration rate (GFR) and renal blood flow (RBF), with an attenuated plasma 
natriuretic peptide and renal cyclic guanosine 3’,5’-monophosphate (cGMP) response to 
saline volume expansion (VE).   The mechanism for the renal dysfunction and 
attenuated renal cGMP response to VE is undefined.  
 
Cyclic GMP is the second messenger of the natriuretic peptide system (NPS) 
and the nitric oxide system (NO) and plays an important role in the preservation of 
myocardial, vascular, and renal function.  Hence, disruption of this signal transduction 
process may contribute to the development of cardiorenal dysfunction(1). Type V 
phosphodiesterase (PDEV) metabolizes cGMP and is abundant in the kidney, 
vasculature, and has been recently reported in the heart.(2,3)  We and others have 
demonstrated that renal PDEV is up-regulated in experimental HF and may lead to the 
attenuation of renal cGMP generation in response to both endogenous and exogenous 
BNP, thus serving as a mechanism for renal resistance to BNP. Furthermore, in 
experimental overt HF, 10 days of PDEV inhibition treatment resulted in reduction of left 
ventricular (LV) mass, increased LV fractional shortening and cardiac output.  
Furthermore, chronic PDEV inhibition did enhance the renal actions of exogenous BNP, 
specifically improving GFR and renal cGMP generation.(4)  PDEV inhibitors are FDA 
approved for erectile dysfunction and pulmonary hypertension. 
 
Objective: To determine the effect of 12 weeks of chronic PDEV inhibition with 
Tadalafil  versus placebo  on basal cardiorenal and humoral function and on the 
integrated cardiorenal and humoral response to acute sodium loading in subjects 
with PSD and renal dysfunction.  
 
Hypotheses:  
1. Chronic PDEV inhibition with Tadalafil will result in the improvement of 
renal function measured by glomerular filtration rate (GFR) as compared 
to placebo in subjects with PSD and renal dysfunction. 
2. Chronic PDEV inhibition with Tadalafil will result in the improvement 
urinary sodium excretion and urinary cGMP excretion in response to acute 
sodium loading as compared to placebo in subjects with PSD and renal 
dysfunction. 
 
Primary end points: 
1. Change in GFR from baseline after 12 weeks of chronic Tadalafil versus 
placebo. 

4 
 
2. Change in urinary sodium excretion and urinary cGMP excretion in 
response to acute sodium loading from baseline after 12 weeks of chronic 
Tadalafil versus placebo. 
 
Secondary end point: 
1. Change in LVEF, dimensions and diastolic function from baseline after 12 
weeks of chronic Tadalafil versus placebo. 
2. Change in blood pressure (BP), heart rate, right ventricular (RV) end- 
systolic pressure and RV functions. 
 
 
Study design:  
This will be a single center double blind placebo-controlled design. Subjects 
will be randomized in a 2:1 design, to the Tadalafil alone group  or placebo .  
 
Study population 
A total of 45  patients with PSD as defined by an ejection fraction of equal or less than 
40%,(assessed within 36 months of enrollment) If patient’s EF was assessed greater 
than 36 months, the PI will performed an assessment of the LV EF during the screening 
visit using an hand-held echo machine.  If EF is  equal or less 40% the patient will be 
enrolled.  The patient will receive compressive echo assessment during the study. 
Also having  no clinical signs or symptoms of congestive heart failure, a minimal 
distance on 6-minute walk of equal or >450 meters will be recruited and calculated 
creatinine clearance of equal or less than 90 ml/min and greater than 30 ml/min, using 
the MDRD formula assessed within the past 24 months. If the subject is not able to walk 
450 meters due to pain in hips and knees and not fatigue or shortness of breath than 
they will still qualify for the protocol.  
 
  Subjects who enroll that had previously participated in in our other PSD protocol IRB 
11-004257, we will be able to use the data from the screening visit such as labs, cardiac 
exam, 6 minute walk and dietician visit   
Exclusion criteria: 
 
• 
Current or anticipated future need for nitrate therapy 
• 
Systolic blood pressure < 90 mmHg or > 180 mm Hg 
• 
Diastolic blood pressure < 40 mmHg or > 100 mmHg 
• 
Patients taking alpha antagonists or cytochrome P450 3A4 inhibitors 
(ketoconazole, itraconazole, erythromycin, saquinavir, cimetidine or serum 
proteases inhibitors for HIV) who cannot be taken off these medications for the 
duration of the study. 
• 
Patients taking the following selective alpha blockers and who are unable to stop 
for the duration of the study: 
o  Alfuzosin 
o Prazosin 
o Doxazosin 
o Tamsulosin 
o Terazosin 

5 
 
o Silodosin 
o Also guanylate cyclase stimulators (Riociguat)" 
o  
 
• 
Patients with retinitis pigmentosa, previous diagnosis of nonischemic optic 
neuropathy, untreated proliferative retinopathy or unexplained visual disturbance 
• 
Patients with sickle cell anemia, multiple myeloma, leukemia or penile deformities 
placing them at risk for priapism (angulation, cavernosal fibrosis or Peyronie's 
disease)  
• 
Patients with an allergy to iodine. 
• 
Patients on PDEV inhibition for pulmonary hypertension 
• 
Patients on PDEV inhibition for erectile dysfunction who are not willing to stop the 
medication for the duration of the study 
• 
Valve disease (> moderate aortic or mitral stenosis; > moderate aortic or mitral 
regurgitation) 
• 
Obstructive Hypertrophic cardiomyopathy 
• 
Infiltrative or inflammatory myocardial disease (amyloid, sarcoid) 
• 
Pericardial disease 
• 
Have experienced a myocardial infarction or unstable angina, or have undergone 
percutaneous transluminal coronary angiography (PTCA) or coronary artery 
bypass grafting (CABG) within 60 days prior to consent, or requires either PTCA 
or CABG at the time of consent  
• 
Severe congenital heart diseases 
• 
Sustained ventricular tachycardia or ventricular fibrillation within 14 days of 
screening 
• 
Second or third degree heart block without a permanent cardiac pacemaker 
• 
Stroke within 3 months of screening or other evidence of significantly 
compromised CNS perfusion 
• 
Hemoglobin <9 g/dL 
• 
Patients with severe liver disease (AST > 3x normal, alkaline phosphatase or 
bilirubin > 2x normal)  
• 
Serum sodium of  < 125 mEq/dL or > 150 mEq/dL 
• 
Serum potassium of < 3.2 mEq/dL or > 5.9 mEq/dL 
• 
Prior diagnosis of intrinsic renal diseases including renal artery stenosis of > 50% 
• 
Peritoneal or hemodialysis within 90 days or anticipation that dialysis or 
ultrafiltration of any form will be required during the study period  
• 
Less than 21 years of age 
• 
Pregnant or nursing women.  
• 
Women of child bearing potential who do not have a negative pregnancy test at 
study entry and who are not using effective contraception 
• 
Non-cardiac condition limiting life expectancy to less than one year, per physician 
judgment 
• 
Other acute or chronic medical conditions or laboratory abnormality which may 
increase the risks associated with study participation or may interfere with 
interpretation of the data 
• 
Received an investigational drug within 1 month prior to dosing 
• 
In the opinion of the investigator is unlikely to comply with the study protocol or is 
unsuitable for any reasons 

6 
 
 
 
Study protocol 
At the consent visit, diet instructions will be given by study personnel and 
baseline whole blood count, Hgb A1C, electrolyte panel, AST and Bilirubin will be 
obtained. . Prior to the first overnight stay the subjects will be  given instructions on a no 
added salt diet (120 mEq Na/day) which will be maintained throughout the study period.   
If subjects calculated creatinine clearance is not between 30 to 90 ml/min 
using the MDRD formula the subject will be excluded from the study. Also at 
consent visit the 6 minute walk will be done to determine eligibility and a physical exam 
along with vital signs, height and weight will be done. Twenty-four hour urine collection 
will be obtained one day prior to the active study day for assessment of baseline sodium 
excretion, creatinine clearance and microalbuminuria. For instances where subjects are 
not able to collect urine for 24 hours prior a 12 hr collection will be done.  
Therapy with ACE inhibitor or Angiotensin receptor blockers or other 
vasodilators, beta-receptor antagonists, Digoxin and antiarrhythmic medications will be 
allowed, however, at stable doses for two weeks prior to the study date. 
 
Subjects will be admitted to the CRU on the evening before the active study day. 
They will be able to order a no-added salt meal and will be NPO after midnight until the 
last renal clearance blood draw the next day. Bladder scan will be carried out to assess 
for urine retention on the active study day, subjects take their medications upon 
awakening, however, diabetics will hold their diabetic medications until after the last 
renal clearance test then they will be able to order a regular diet meal and take their 
diabetic medications. During the first 15 minutes, two standard intravenous (IV) 
catheters will be placed (one in each arm). One catheter will be used for infusion and the 
other (in the contralateral arm) for blood sampling.  Subjects will be asked to drink 
5ml/Kg of water to insure sufficient urinary flow. A priming dose (calculated according to 
body size) of Iothalamate, to measure glomerular filtration rate (GFR)) is infused, 
followed by a constant rate IV sustaining dose (calculated according to estimated kidney 
function) of Iothalamate.  The subjects will be asked to empty their bladder 
spontaneously every thirty minutes (if subjects are unable to void every thirty minutes, a 
urinary catheter can be used upon consent).  Extra fluids may be given if subjects are 
not able to void and the amount recorded in the total of fluids given. Throughout the 
study, at the end of each 30-minute clearance period, subjects will be asked to drink an 
amount of water equivalent to the sum of the blood losses and the urinary flow. After an 
equilibration period of 45 minutes, a 30-minute baseline renal clearance will be carried 
out and will also include tests for adiponectin and glycerol. Urinary samples for 
determination of volume, urinary sodium excretion (UNaV), cGMP, CNP, Iothalmate, will 
be obtained at the end of the clearance period.  Venous blood samples for Iothalmate, 
sodium, ANP, BNP, cGMP, renin, angiotensin II, CNP and aldosterone will be obtained 
at the middle of the clearance period. Collection of blood at baseline, during and after 
sodium load will be stored for future DNA/Protein analysis. 
  Blood pressure will be measured at 20-minute intervals by using automatic blood 
pressure cuff, and heart rate will be continuously monitored by electrocardiography. 
Echocardiography will be performed during these baseline clearances to 
determine left atrial (LA) and left ventricular (LV) volumes, systolic and diastolic 
function, right ventricular end systolic pressure and function.  If patients LVEF is 
great than 40%, the patient will then be excluded from the rest of the study. 
Echocardiography will be performed during these baseline clearances to determine left 
atrial (LA) and LV volumes and systolic and diastolic function. 

7 
 
 
 
After the baseline clearance the acute saline load will be administered (normal saline 
0.9% 0.25 ml/kg/min for 1 hour).  During the 1 hour saline load, one 30-minute clearance 
(as outlined above) will be repeated with the subjects in supine position after which a 
second 30-minute clearance will be repeated with the subject sitting or the head of the 
bed up. As above, blood samples are collected midway during each clearance and urine 
samples are obtained every 30 minutes. Echocardiography will be repeated immediately 
after the end of the saline infusion. 
 
At the completion of the baseline renal clearance periods and response to acute sodium 
load, subjects will be randomized to Tadalafil or placebo. Subjects will be randomized 
in a 2:1 fashion. The randomization schedule will be provided by the Department of 
Biostatistics, implemented by the Mayo Pharmacy and administered by the CRU staff.   
 
 
All subjects will initially take 1 tab Tadalafil (5mg) or Placebo. The blood pressure will be 
checked prior to administering the drug. Thereafter, both blood pressure and heart rate 
will continue to be monitored every 20 minutes for the next 4 hours. If after the first dose 
of study drug if patient’s systolic blood pressure is < 85 mmHg systolic and has 
symptoms of hypotension e.g. lightheadedness, dizziness, feeling faint, blurred vision, 
the study drug will be stopped however the subject will continue in the study.  After 2 
hours if blood pressure is >95 systolic then give 1 more (5 mg) of Tadalafil or placebo 
and monitor blood pressure for 2 hours. If blood pressure is >95 then dismiss subject on 
2 (5 mg) tabs of tadalafil or placebo. If blood pressure is between 90 – 95 mmHg 
systolic, then dismiss on 1 (5 mg) tab of Tadalafil or placebo to be maintained on this 
dose for the remainder of the study and not be increased   
 
Subjects will be instructed to take their blood pressure daily for 12 weeks.  Subjects will 
also have access to a 24-hour phone number should they have any questions or 
develop any side effects.   
 
At 2 weeks (± 5 days) from dismissal if blood pressure is> 100 than add 1 (5 mg) tab of 
Tadalafil or placebo to make a total of 3 (5mg) tabs of Tadalafil or placebo. 
 
At 4 weeks(± 5 days)  if blood pressure is > 100 add 1 (5 mg) tab to make a total of 4 (5 
mg Tadalafil or placebo. 
 
The PI can reduce the dose of Tadalafil or placebo if subjects blood pressure is < 90 
and/or has symptoms of hypotension e.g. lightheadedness, dizziness, feeling faint, 
blurred vision.   
 
Subjects will return after one week (± 4 days) for electrolyte check. For patients who live 
more than 25 miles away we will try to arrange this visit with the patient’s local physician. 
They will also receive a weekly phone call to review status.   
 
After six weeks (±5 days)  , subjects will repeat blood draw for safety labs ( electrolytes). 
For patients who do not live more than 25 miles away we will try to arrange this visit with 
the patient’s local physician. 
  
At the end of the twelve-week study period (+ or – 8 days), subjects will be admitted to 
the CRU the afternoon prior to the renal clearance study. We will get an hgb A1C with 
the evening blood draw for the creatinine. Echocardiography, renal clearance, humoral 

8 
 
determination, adiponectin, glycerol tests and acute saline load will be performed in the 
same manner as the baseline study.  Subjects will also perform a 24-hour urine 
collection the day prior to their return visit for determination of sodium excretion and 
creatinine clearance.  Subjects will be dismissed after the renal clearance study.  
  
Sample size and statistical analysis 
The sample size calculation and statistical analysis have been designed in collaboration 
with the Division of Biomedical Statistics and Informatics, (Kent Bailey, Ph.D) . 
 
 
The primary analyses will be a couple of 2-sample comparisons (2-sample t-test) of the 
effects of interest: Changes in glomerular filtration rate, sodium excretion, urinary cGMP 
excretion, left ventricular end systolic and diastolic volume.  To further investigate this 
relationship we will also do an analysis of covariance to look at the group differences on 
the final effects of the drug after adjusting for the before drug measurements. Values will 
be expressed as the mean + SD. A statistically significant difference will be considered 
to be present when p<0.017.   
 
Sample size calculation: Based on our completed specific aims 1 of the current funding 
cycle, we were able to construct the magnitude of difference that could be detected for 
each of the seven parameters. With 26 subjects in the active treatment group and 13 
subjects in the placebo group, we have 80% power to detect the differences as reported 
in the second table.  
The table below summarizes preliminary data on these within subject changes: 
Comparison Between Treatment Groups 
Change From Baseline to After Volume Expansion 
Variable 
Placebo 
(N=18) 
BNP 
(N=18) 
P-
value 
GFR (U1-U3 Avg to U4) 
-1.2 ± 12.6   
5.1 ± 16.0   
0.20 
Sodium Excretion (U1-U3 Avg to U4) 
-17.4 ± 63.1   
84.1 ± 133.2  
0.007 
Renal Plasma Flow (U1-U3 Avg to U4) 
5.7 ± 52.1   
34.5 ± 79.1   
0.21 
LV Ejection Frac. (Base to Aft Vol Exp) 
3.3 ± 3.1    
4.1 ± 2.3    
0.40 
LV Diastolic Index (Base to Aft Vol Exp) 
-2.2 ± 6.4    
-7.3 ± 10.1   
0.08 
LV Systolic Index (Base to Aft Vol Exp) 
-3.4 ± 3.0    
-5.8 ± 3.4    
0.036 
Urinary cGMP (Baseline to 30 Min) 
57.1 ± 104.3  
268.7 ± 282.3  
0.003 
 
Based on these estimates, we obtain the following detectable differences between 
2 groups: 
 
 
Detectable difference between the PDEV inhibition and 
placebo group for the same parameter(80% power, n=26, 
alpha=0.25);Two-sample t-test 
GFR 
15.1 
Sodium 
Excretion 
125.4 
Renal Plasma 
Flow 
74.5 
LV EF 
2.2 

9 
 
LV Diastolic 
Index 
9.5 
LV Systolic Index 2.1 
Urinary cGMP 
265.7 
 
It is the primary goal of the study to detect an improvement of GFR of at least 15 
ml/min, which is considered a clinically meaningful improvement of GFR.  The 
detectable differences in the other 6 parameters are plausible and of interest as well. 
 
Recruitment of subjects:  
Subjects will be recruited from the echo database and will receive a reimbursement of 
$300 for participation in the study. 
  
Assessment of systolic and diastolic function by echocardiography: Transthoracic 
echocardiography will be performed according to the standard clinical Amercian Society 
of Echocardiography methods. 
 
 
Analytic methods 
Both plasma and urine concentration of Iothalmate will be determined by the Mayo Core 
Renal lab. Glomerular filtration rate (GFR) will be calculated using Iothalmate clearance  
 
GFR (ml / min)  =     U   x   V              
 
                P                                                                            
Where:    U = urine concentration; P = plasma concentration;  V = urine flow (mL/ 
min) 
Plasma and urine will be analyzed for sodium with the Beckman ion-selective analyzer.  
Urine creatinine will be measured by the Mayo Core Renal Laboratory.  Venous blood 
for hormone analysis will be collected in heparin and EDTA tubes and immediately 
placed on ice.  After centrifugation at 2,500 rpm at 4C, the plasma will be decanted and 
stored at -80C until analysis.  Specific plasma radioimmunoassays include renin, 
aldosterone, angiotensin II, ANP, BNP and cGMP.  Urine for cGMP and CNP 
radioimmunoassays will also be collected on ice as previously described. 
 
 
 
PROTECTION OF HUMAN SUBJECTS 
 
a) Human Subject Involvement and Characteristics 
These protocols will not involve special classes of subjects, such as fetus, 
neonates, pregnant women, children, prisoners, institutionalized individuals, or others 
who may be considered vulnerable populations.  
 
The specific subject population is as follows: 
 
PSD-will consist of 45 subjects with an ejection fraction of less than 40% with no clinical 
signs or symptoms of congestive heart failure; a minimal distance on 6-minute walk of 
>450 meters and calculated creatinine clearance of equal or less than 60 ml/min and 
greater than 30 ml/min, using the MDRD formula assessed within the past 24 months. A 
6-minute walk distance of 450 meters was the average distance achieved by NYHA 
class I patients in the SOLVD trial and is an objective marker of clinical status. If the 
subject is not able to walk 450 meters due to pain in hips and knees and not fatigue or 
shortness of breath than they will still qualify for the protocol.  

10 
 
 
 
b) Source of Materials  
Plasma samples, urine samples echocardiographic data and clinical data will be 
used entirely for research purposes. Patient identifiers will not be released outside of 
Mayo and any publications will exclude any kind of patient identifiers that could be 
correlated with the specific patient.  Limited access data set will be made available 
according the NHLBI guidelines . 
c) Potential Risks and Adequacy of Protection against Risks 
 
The overall risk for participation in the protocol is small and the main concern is that the 
addition of PDEV inhibition (Tadalafil) may result in hypotension.  The medication will be 
started in the CTSA CRU under close monitoring; hence, the study has extremely little 
risk of causing irreversible consequence on the patients. 
In addition the subjects will measure their blood pressure daily at home and will be 
instructed to report a blood pressure below 95 and or hypotension symptoms e.g. 
lightheadedness, dizziness, feeling faint, blurred vision. They will receive a weekly 
phone call and safety labs at week 1 and 6.  
 
The PI can reduce the dose if subject has a blood pressure < 90 and or has symptoms 
of hypotension e.g. lightheadedness, dizziness, feeling faint, blurred vision.  
 
Tadalafil is a PDEV inhibitor which is FDA approved for the management of erectile 
dysfunction and pulmonary hypertension.  The recommended dose for erectile 
dysfunction is 5 mg/day and for pulmonary hypertension in patients with renal 
dysfunction (eGFR<30 <80 ml/min ) is 20 mg once a day. 
 
Common side effects include; Flushing (1% to 13% ),Indigestion (4% to 13% ), 
Nausea (up to 11% ); Backache (3% to 12% );Myalgia (1% to 14% ); Headache (3% to 
42% ); Nasopharyngitis (2% to 13% ) and Respiratory tract infection (7% to 13% ).  
 
Rare side effects include: Angina (less than 2% ), Chest pain (less than 2% ), 
Heart failure, Myocardial infarction (less than 2% ), Tachycardia (less than 2%, Stevens-
Johnson syndrome, Cerebral hemorrhage, Cerebrovascular accident, Seizure, Non-
arteritic ischemic optic neuropathy, Retinal artery occlusion, Thrombosis of retinal vein, 
Decreased hearing, Sudden onset (less than 2% ), Sudden hearing loss (less than 2% ). 
Priapism. 
 
Acute saline loading: These studies require acute saline loading with normal saline 
0.9% 0.25 ml/kg/min for 1 hour.  Previous studies by Volpe and others have shown that 
this is tolerated well. In the current funding cycle, we have completed studies in 
approximately 120 patients with no adverse event of fluid overload.  There is small risk 
of causing fluid overload, however, the subjects will be closely monitored closely in the 
CRU and the study will be terminated if the subject develops and signs or symptoms of 
fluid overload and will be treated appropriately with IV diuretics.   
 
To protect the patients against the risk of hypotension, the following measure are 
incorporated in the protocol: 
• 
Screening and application of exclusion criteria will minimize risks  
• 
Medication will be initiated in the CTSA CRU under close monitoring.  
 

11 
 
The following stopping rule will be applied to ensure patient safety: 
The blood pressure will be checked prior to giving the drug.  
 
• 
If after the first dose of study drug if patient’s systolic blood pressure is < 85 
mmHg systolic and has symptoms of hypotension e.g. lightheadedness, 
dizziness, feeling faint, blurred vision, then the study drug will be stopped 
however the subject will continue in the study. 
• 
Any patient that experiences any adverse events as defined below during the 
study the study drug will be reduced or stopped.  The adverse events include: 
hypotension as defined by a) any clinical symptoms of hypotension e.g. 
lightheadedness, dizziness, feeling faint, blurred vision and b) if systolic blood 
pressure is < 85 mmHg; b) symptoms of heart failure for > 45 minutes; c) allergic 
reaction to the drug and others unexpected adverse events which is deemed to 
be clinically significant by the investigator. 
 
Plan of intervention in the event of adverse effects to the subjects. 
• 
In the CRU, if the patient does develop hypotension, as defined by a) any clinical 
symptoms of hypotension e.g. lightheadedness, dizziness, feeling faint, blurred 
vision and b) if systolic blood pressure is < 85 mmHg; the clinical care team will 
manage that according to the standard resuscitative procedure: Trendelenburg 
position, give fluid IV, use of vasopressor if necessary 
 
Other potential minor risk includes: 
 
The risks of blood drawing include bleeding at the puncture site, bruising and 
pain. These risks occur in a very small portion of the population.  
 
This protocol may be hazardous to an unborn child.  There is no medical 
information to determine whether there are significant risks to a fetus carried by a mother 
who is participating in this study.  Therefore, female participants must be 
postmenopausal or have been surgically sterilized or have a negative pregnancy test 
and must agree to use a reliable method of contraception until study completion. 
Methods of contraception include: birth control pill/implants/injections, intrauterine 
devices, spermicide, diaphragm or condoms.    
 
Iothalamate contains a small amount of iodine and for persons allergic to iodine, 
this could pose a higher risk for an allergic reaction. To date in more than 5,000 patients, 
there have been only rare allergic reactions (one or two) when the solution has been 
used for this type of test. The amount of the material injected for this test will be 
approximately the same as that used in a similar kidney function test performed on a 
routine basis (approximately 250 tests per month) in the Renal Function Laboratory. 
However, patients with a history of an allergic reaction to iodine should not participate in 
this study.  
 
d) Recruitment and Informed Consent 
Subjects will be recruited at the Mayo Clinic from the Heart Failure Clinic, 
Community Internal Medicine, and General Internal Medicine and referrals from 
physicians in the Mayo Health care system. In addition, we also now have in place a 
new web-based patient identification system developed at Mayo by the Cardiovascular 

12 
 
Research 
Program. 
This 
system 
can 
be 
cross-referenced 
with 
the 
Mayo 
Echocardiography laboratory database and can identify patients with left ventricular 
systolic or diastolic dysfunction without clinical diagnosis of CHF throughout the entire 
Mayo system.   
 
Patients will be approached for participation in the study in one the following ways: 
• 
Approached at the clinic 
• 
Letters of invitation or phone calls to patients that we have identified through our 
web-based patient identification system and colleague’s referrals. Both the letters 
of invitation and phone scripts will be reviewed and approved by Mayo IRB. 
• 
We will also call or send a letter to a list of participants who enrolled in our 
previous PPG studies 
 
Upon identification of a subject, the study will be explained in detail by the investigators 
or study co-coordinator, the consent form reviewed questions answered and the consent 
form signed.  The information in the consent form that will be reviewed is as follows: 
 
• 
Why is this research study being done? 
 
• 
How many people will take part in this research study? 
 
• 
What will happen in this research study? 
 
• 
How long will I be in this research study? 
• 
Are there reasons I might leave this research study early? 
• 
Will any biological sample(s) be stored and used for research in the future? 
 
• 
How do researchers from other institutions get the sample? 
 
• 
What are the risks of this research study? 
 
• 
Are there benefits to taking part in this research study? 
 
• 
Will I be compensated for the study? 
 
• 
What other choices do I have if I don’t take part in this research study? 
 
• 
Will I need to pay for the tests and procedures? 
 
• 
What happens if I am injured because I took part in this research study? 
 
• 
What are my rights if I take part in this research study? 
 
• 
Who can answer my questions? 
e) Potential Benefits of the Proposed Research to the Subjects and Others 

13 
 
Subjects participating will not benefit from this study..  More importantly, this 
study will provide us new insights into the human cardiorenal syndrome that may allow 
us to develop new therapeutic strategies, which may benefit others with the same 
problem.   
 
f) Importance of Knowledge to be Gained 
This research will provide us new insights into the human preclinical left 
ventricular and renal dysfunction that may allow us to develop new therapeutic 
strategies, which may benefit others with the same problem. 
 
g) Data and Safety Monitoring Plan 
In accordance with the NHLBI requirements the following is the data and safety 
monitoring plan (DSMP): 
Data and Safety Monitoring Board 
The data and safety monitoring board (DSMB) will include Dr Richard Rodeheffer and Dr 
Lyle Olson. One of the members will be appointed the executive secretary (ES).   
DSMB ES is responsible for setting up DSMB meetings, and for generating official, 
written minutes.   
 
The DSMB will review all the Unanticipated Problem Involving Risk to Subjects or 
Others (UPIRTSO).  The DSMB will also review all the adverse events at 3 time 
points: a) after 10 subjects; b) after 20 subjects; c) after 30 patients have 
completed the protocol and every 6 months after that.   
 
Stopping Rules 
 
The study sample size is too small for the application of traditional stopping rules.  
However, due to the potential for increased risk of hypotension, the DSMB will evaluate 
the number of patients who develop hypotension.   If the DSMB is concerned about the 
number of these adverse clinical events, the DSMB will inform the NHLBI and Mayo IRB 
either that the protocol needs to be modified or enrollment should be suspended. 
 
Adverse Event and Serious Adverse Event Reporting and Follow-up 
The following are in accordance with the NHLBI, Office for Human Research Protections 
(OHRP) and Mayo Clinic IRB policies. 
Definitions: 
1) Adverse Event: As defined by OHRP, an adverse event is any untoward or 
unfavorable medical occurrence in a human subject, including any abnormal sign (for 
example, abnormal physical exam or laboratory finding), symptom, or disease, 
temporally associated with the subject’s participation in the research, whether or not 
considered related to the subject’s participation in the research. Adverse events 
encompass both physical and psychological harms.  
 
2) Serious Adverse Events include those which: 
• 
Are fatal or life threatening;  
• 
Result in significant or persistent disability;  
• 
Require or prolong hospitalization;  
• 
Result in a congenital anomaly/birth defect;  
• 
Represent other significant hazards or potentially serious harm to research 
subjects or others, in the opinion of the investigators.  

14 
 
 
3) Unanticipated Problem Involving Risk to Subjects or Others (UPIRTSO):  
 
Mayo Clinic's IRB and OHRP defines unanticipated problem/event involving risk to 
subjects or others (UPIRTSO) as any problem or event that was 1) serious; 2) 
unanticipated; AND 3) at least possibly related to the research procedures. 
 
Serious: Serious problems/events can be well defined and include death; life 
threatening adverse experience; hospitalization: inpatient, new, or prolonged; 
disability/incapacity: persistent or significant; birth defect/anomaly; and/or per protocol 
OR may be problems/events that in the opinion of the local Investigator may have 
adversely affected the rights, safety, or welfare of the subjects or others, or substantially 
compromised the research data. 
 
Unanticipated: (unexpected) problems/events are those that are not already described 
as potential risks in the consent form, not listed in the Investigator's Brochure, or not part 
of an underlying disease. A problem/event is "unanticipated" when it was unforeseeable 
at the time of its occurrence. A problem/event is "unanticipated" when it occurs at an 
increased frequency or at an increased severity than expected. 
 
Related: A problem/event is "related" if it is possibly, probably or definitely related to the 
research study 
 
Adverse Event Reporting 
All non-serious adverse events (AEs) will include those that occur from randomization 
through 7 days after the completion of the second study day at the CTSA CRU. 
a) Report to DSMB 
 
As stated above, the DSMB will also review all the AEs at 3 time points: 
a) after 10 subjects; b) after 20 subjects; c) after 30 patients have completed the 
protocol and every 6 months after that.  
b) Report Mayo IRB 
  
All AEs will be reported to the Mayo IRB during the yearly progress report for IRB 
approval. 
 
c) Report NHLIBI 
 
The AEs will be reported to the NHLBI during the yearly non-competitive 
renewal. 
 
Serious Adverse Event Reporting 
All serious adverse events (SAEs) will include those that occur from randomization 
through 7 days after the second study day 
a) Report to DSMB 
 
If the Serious AE involves death or a life-threatening event the PI will a contact a  
member of the DSMB within 5 days to determine the relationship between the event and 
the study intervention. If the event was definitely related, probably related or possibly 
related to the study intervention, the PI will call the PO at NHLBI and submit the 
UPIRTSO form to Mayo IRB within 5 days 
 
Regardless of causality, the investigator will report Unanticipated SAE to 
DSMB within 5 days of knowledge of the event to determine the relationship between the 
event and the study intervention and include any relevant documents such as medical 
record notations or reports with the name and medical record number of the individual 

15 
 
removed. Assess whether protocol modifications are required as a result of the 
UPIRTSO. The Investigator must provide an explanation on the UPIRTSO form 
explaining what corrective actions have already been taken.  
If the event was definitely related, probably related or possibly related to the study 
intervention, the PI will inform the PO at NHLBI and submit the UPIRTSO form to Mayo 
IRB within 5 days.  The investigator will complete and submit a follow-up report when 
additional relevant information (final diagnosis, outcome, results of specific 
investigations, etc.) becomes available.  The investigator will follow all reportable events 
until resolution or stabilization. The DSMB will follow all SAEs until resolution, 
stabilization, or last patient completes follow up, whichever occurs first.  Any serious 
adverse event that is ongoing when a patient completes his/her participation in the trial 
will be followed by the investigator until any of the following occurs: 
• The event resolves or stabilizes. 
• The event returns to baseline condition or value (if a baseline value is available). 
 
b) Mayo IRB 
Regardless of causality, the investigator will report Unanticipated SAE to DSMB 
within 5 days of knowledge of the event to determine the relationship between the event 
and the study intervention. If the event was definitely related, probably related or 
possibly related to the study intervention, the PI will submit the UPIRTSO form to Mayo 
IRB within 5 days  
 
The following section is the Mayo IRB’s policy for handing a UPIRTSO report: 
Mayo IRB Specialist Responsibilities  
Upon receipt of a UPIRTSO, the Specialist shall review the report within one working 
day.  
1. 
Problems/Events that meet the definition of UPIRTSO are referred 
to a Chair or Vice Chair for determining whether an Administrative 
Hold is necessary as set forth in IRB Policy II.B, and assigned to 
the next available Full Committee.  
2. 
Problems/Events that do not clearly meet the definition of 
UPIRTSO shall be referred to a Chair or Vice Chair to make the 
determination for appropriate triage and whether an Administrative 
Hold is necessary as set forth in IRB Policy II.B. [1]  
3. 
Problems/Events that are determined to be Non-UPIRTSOs will 
be returned to Investigator with instructions to submit in 
accordance with Section I.C of this procedure.  
For those problems/events determined to be UPIRTSOs, the Specialist shall ensure all 
IRB Committee Members have access to the following documents for review at the next 
available meeting:  
• 
The UPIRTSO form;  
• 
The DSMB or safety report, if applicable;  
• 
Supplemental material submitted with the report;  
• 
A modification request, if applicable;  
• 
The current IRB approved application and consent document;  

16 
 
• 
The study protocol;  
• 
The Investigator's Brochure, if applicable; and  
• 
Any other pertinent materials.  
The Specialist will generate a minute item describing the Full Committee's decision 
regarding the UPIRTSO. The minute item will be reviewed and approved by the Full 
Committee and sent to the Investigator.  
The Specialist will complete all appropriate IRB database entries.  
Mayo IRB Committee Responsibilities  
A. The Chair or Vice Chair will receive UPIRTSO reports from the Specialist in 
accordance with Section II.A.1, 2 of this procedure.  
B. Problems/Events that are determined by the Chair or Vice Chair to be Non-
UPIRTSOs will be returned to Investigator with instructions to submit in 
accordance with Section II.A.3 of this procedure.  
C. If the Chair or Vice Chair determines the problem/event is a UPIRTSO or cannot 
make a determination, the report will be forwarded to the Full IRB Committee to 
make these decisions.  
D. A primary reviewer will be assigned. All IRB Committee Members will receive a 
copy of the UPIRTSO form and supporting documents provided by the 
Investigator to assist in determining whether the problem/event meets the 
applicable criteria.  
E. If the IRB determines that more information is needed, it may postpone a 
decision while awaiting the requested information. In such cases, the IRB will 
consider the appropriateness of an "Administrative Hold" on the research until a 
final determination is made.  
F. Problems/events that are determined by the IRB to be Non-UPIRTSOs will be 
documented as set forth in IRB Policy III.G.  
G. If the IRB determines that the problem/event meets all three criteria, (serious, 
unanticipated, and related), the problem/event will be considered a UPIRTSO 
and the following actions may take place:  
 
 
The IRB may:  
a. Approve the report with no changes;  
b. Approve the report with changes to the protocol requested 
in the modification;  
c. Request a meeting with the Investigator;  
d. Request further information from the Investigator, Data 
Safety Monitoring Board (DSMB) or other monitoring 
bodies;  
e. Increase the frequency of continuing progress report 
review;  
f. Impose additional monitoring;  
g. Ask the Investigator to place the study on "Administrative 
Hold" pending receipt of further information;  
h. Suspend the study for cause as set forth in IRB Policy II.B 
with:  
I. 
Suspension of recruitment;  

17 
 
II. 
Suspension of screening and enrollment;  
III. 
Suspension of intervention and interaction; or  
IV. 
Suspension of follow-up.  
i. Terminate the study for cause as set forth in IRB Policy II.B. 
• 
The problem/event will be reported as set forth in IRB 
Policy II.C.  
• 
The IRB will consider whether the problem represents 
serious or continuing non-compliance as set forth in 
IRB Policy II.C.[3]  
• 
In the case of changes in the protocol taken without 
prior IRB review to eliminate apparent immediate 
hazard to a research subject, the IRB will consider 
whether the changes were consistent with the 
protection of the rights and welfare of subjects.  
 
Reporting to NHLBI 
 
In accordance with the NHLBI policy, all investigators conducting clinical studies 
supported by the NHLBI must report expected and unexpected serious adverse events 
to the NHLBI. The investigator must forward copies of all reports of serious adverse 
events (expected and unexpected) when they are submitted to the IRB and DSMB. 
Adverse events will be reported in annual reports.  
Expedited reporting is required for serious adverse events that are unexpected. 
• 
If the unexpected events are life-threatening or fatal, they should be reported 
within 7 calendar days.    
• 
All other serious adverse events that are unexpected should be reported within 15 
calendar days.  
Copies of reports are sent to the NHLBI Program or Project Officer responsible for the 
study. 
 
INCLUSION OF WOMEN 
It is important to define and understand the difference in the pathophysiology of PSD 
and PDD between women and men.  Every effort will be made to include equal number 
of male and females in the proposed protocols, with a focus to recruit women from the 
Mayo Women’s Heart Clinic.  Experience form the Mayo CRU in 1996-97 showed that 
50% of the 2320 patients enrolled in the CRU protocols were women.  Separate analysis 
will be performed on the above data to compare the effect of gender on the integrated 
cardiorenal and humoral function in all the protocols. 
 
INCLUSION OF MINORITIES 
Studies have demonstrated a high prevalence of preclinical LV dysfunction in minority 
populations.  Every effort will be made to recruit minorities in the proposed studies.  
Subjects will not be excluded from participating in the studies based on race or ethnicity.  
While the vast majority of residents in Rochester, Minnesota and the surrounding 
communities are White, population demographics have changed over the past decade 
due to emigrants from Somalia and from Southeast Asia.   
Olmsted County census data from 2000 and American Community Survey for Rochester 
MN from 2005-2007, are listed below.  Rochester city data from July 2007 shows that 

18 
 
the African American, non-Hispanic population has increased to 4.9% and that the 
Hispanic population has increased to 3.5%. 
Overall Local Figures for Olmsted County Population (percent)-2000 
Census 
 
Experience in Mayo CRU-based protocols has shown that minority patient’s recruitment 
increased from 2.8% in 1992-93 to 15.2 % in 1997.  This is in part due to the special 
initiative undertaken to help ensure the participation of underrepresented populations in 
clinical research.  Miriam A. Marquez, Ph.D., Director of the Mayo Clinic office of 
Diversity in Clinical Research, and her staff have focused on improving communication 
with local minority groups and on the continuous education and involvement of medical 
and paramedical staff on issues regarding diversity.  This has provided measurable 
success in the local community.   
 
Our target enrollment is to recruit approximately 42 minority subjects for the protocols to 
ensure a minority representation of at least 25% of the study population.  We anticipated 
that 50% of the participants would be female, and 50% male. 7% will be Hispanic, 10% 
Asian, 8% Black not of Hispanic origin and 75% Caucasian. 
 
Our primary strategy to achieve our target minority recruitment is to work with the 
medical and paramedical staff of the Diabetes Clinic, Cardiology Clinic, General Internal 
Medicine Clinic and Echocardiography Laboratory to recruit minority subjects.  My 
clinical study coordinator and research assistant with the help of the Mayo Clinic 
language interpreters will facilitate these efforts.  With the help of Dr Miriam A. Marquez, 
we have developed a complementary community-based educational strategy for 
recruitment of local minority study subjects.  We will also work to establish community 
liaisons with the Multicultural Alliance Network in Olmsted County Minnesota and the 
Rochester Chinese Cultural Association, to provide connection between the Mayo Clinic 
and minority communities. 
 
INCLUSION OF CHILDREN 
The current application is focused on subjects with PSD and PDD which is usually 
consequent to prolonged exposure to cardiovascular risk factors, such a hypertension, 
hypercholestrolemia, smoking, diabetes, coronary artery diseases.  We have excluded 
subjects with significant valvular and congenital heart diseases, which is the most 
common cause of heart failure in children.  Thus we believe that this research topic is 
not relevant to children and justify the exclusion of children form the current application. 
 
 
 
 
 
 
 
 
 
 
American 
Indian 
or Alaskan Native 
Asians or Pacific 
Islander 
Black, not of 
Hispanic Origin 
Hispanic 
White, not of  
Hispanic Origin 
Total 
Male 
0.2% 
2.4% 
0.7% 
0.8% 
44.6% 
51.4% 
Female 
0.1% 
2.4% 
0.4% 
0.7% 
47.7% 
48.6% 
Total 
0.3% 
4.9% 
1.1% 
1.5% 
92.3% 
100% 

19 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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