bluuebunny/crossref_metadata_2025 huggingface dataset:
Statins Are Associated With a Reduced Incidence of Perioperative Mortality After Coronary Artery Bypass Graft Surgery
Authors: Pan Wei , Pintar Tatjana , Anton James , Lee Vei-Vei , Vaughn William K. , Collard Charles D.
Published: September 2004

Background—

Statin therapy in nonsurgical patient populations is associated with a significant reduction in adverse cardiovascular events, including death, myocardial infarction (MI), and stroke. Recently, statin therapy was shown to be associated with a reduced incidence of postoperative mortality in patients undergoing major noncardiac vascular surgery. We investigated the influence of preoperative statin therapy on adverse outcomes after primary coronary artery bypass graft (CABG) surgery.

Methods and Results—

A retrospective cohort study of patients undergoing primary CABG surgery with cardiopulmonary bypass (CPB) (n=1663) between January 1, 2000 and December 31, 2001 at the Texas Heart Institute was performed. Patients were classified into 2 groups: patients receiving preoperative statin therapy (n=943) and patients not receiving preoperative antihyperlipidemic therapy (n=720). To determine if preoperative statin therapy was independently associated with a reduction in the risk of adverse postoperative outcomes, multivariate stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications. Multivariate logistic regression analysis demonstrated that preoperative statin therapy was independently associated with a significant reduction (≈50%) in the risk of 30-day all-cause mortality (3.75% versus 1.80%;
P
<0.05). The adjusted odds ratio for early mortality in patients receiving preoperative statin therapy compared with patients not receiving antihyperlipidemic agents was 0.53 (95% CI, 0.28 to 0.99). Statin therapy was not independently associated with a reduced risk of postoperative MI, cardiac arrhythmias, stroke, or renal dysfunction. In an attempt to further control for selection bias related to the choice of therapy, multivariate analysis of a propensity-matched cohort of 1362 patients revealed that preoperative statin therapy was independently associated with a significant reduction in the composite endpoint of 30-day all-cause mortality and stroke (7.1% versus 4.6%;
P
<0.05).

Conclusions—

Preoperative statin therapy may reduce the risk of early mortality after primary CABG surgery with CPB.
Long-Term Outcome of Isolated Coronary Artery Bypass Surgery in Patients With Severe Left Ventricular Dysfunction
Authors: Appoo Jehangir , Norris Colleen , Merali Sabrina , Graham Michelle M. , Koshal Arvind , Knudtson Merril L. , Ghali William A.
Published: September 2004

Background—

Coronary artery bypass grafting (CABG) is indicated in patients with coronary artery disease and impaired ventricular function. However, earlier studies have suggested that prognosis of patients with severe left ventricular dysfunction is extremely poor. We used the APPROACH registry to derive contemporary estimates of prognosis associated with CABG for this high-risk patient population.

Methods and Results—

The study group consisted of 7841 patients who had isolated CABG in the province of Alberta, Canada between 1996 and 2001. Patients with markedly reduced left ventricular function (ejection fraction [EF] <30%, Lo EF, n =430) were compared with those with moderate reduction in ventricular function (EF 30% to 50%, Med EF, n =2581) and those with normal left ventricular function (EF >50%, normal [Nl] EF, n=4830). The operative mortality was higher in the patient group with Lo EF (4.6%) compared with Med EF and Nl EF groups (3.4% and 1.9%, respectively,
P
<0.001). At 5 years, survival was 77.7% for Lo EF patients compared with 85.5% and 91.2% for Med EF and Nl EF patients, respectively (
P
<0.001). After controlling for other independent variables, the adjusted hazard ratio for death was 1.98 (95% CI, 1.49 to 2.62) for Lo EF relative to Nl EF. The mortality rate at 1 year was significantly lower for Lo EF patients who underwent CABG than it was for nonrevascularized Lo EF patients (risk-adjusted odds ratio, 0.36; 95% CI, 0.24 to 0.55).

Conclusions—

In the modern era of cardiac surgery, CABG can be performed in Lo EF cases with an acceptable perioperative mortality risk. Our estimate of 5-year survival in this high-risk group is better than previously reported in the literature from earlier periods.
Brain Versus Lung: Hierarchy of Feedback Loops in Single-Ventricle Patients With Superior Cavopulmonary Connection
Authors: Fogel Mark A. , Durning Suzanne , Wernovsky Gil , Pollock Avrum N. , Gaynor J. William , Nicolson Susan
Published: September 2004

Background—

CO
2
vasodilates and O
2
vasoconstricts the cerebral vascular bed; the opposite is true in the lungs. When the brain and lungs are connected exclusively in series, which feedback loop predominates is unknown. The circulation of the superior cavopulmonary connection (SCPC) provides a unique physiology to answer this question.

Methods and Results—

To determine cerebral and pulmonary blood flow and to establish the hierarchy of cerebral and pulmonary feedback mechanisms, 12 intubated, ventilated, single-ventricle patients in SCPC physiology (age 2.2±0.5 years) underwent magnetic resonance imaging velocity mapping of their jugular veins and aorta in room air, hypercarbia, and 100% O
2
. Flows in these vessels and arterial blood gases were measured. With 22±6 torr CO
2
(P
co
2
increased from 40 to 63 mm Hg,
P
<0.01), flow to the brain and lungs increased (1.5 to 2.7 L/min per m
2
,
P
=0.0003), P
o
2
improved (48 to 60 mm Hg,
P
=0.0004), and cardiac index increased (4.3 to 5.4 L/min per m
2
,
P
=0.0003). The increased cardiac index accounted for the increased cerebral and pulmonary blood flow (
R
=0.73,
P
=0.02) and cerebral O
2
transport increased by 80% (
P
=0.0005) while preserving body O
2
delivery. Hyperoxia did not change cerebral and pulmonary blood flow; P
o
2
increased 94% (
P
=0.01).

Conclusion—

The cerebral CO
2
feedback loop predominates over the pulmonary one when they directly compete with each other. CO
2
has a major impact on flow distribution whereas O
2
has little impact. Increased CO
2
improves cerebral oxygenation in SCPC patients. This may provide a clue in determining neurological sequelae in SC physiology and may influence timing of Fontan completion.
Atrial Natriuretic Peptide Helps Prevent Late Remodeling After Left Ventricular Aneurysm Repair
Authors: Tsuneyoshi Hiroshi , Nishina Takeshi , Nomoto Takuya , Kanemitsu Hideo , Kawakami Rika , Unimonh Oriyanhan , Nishimura Kazunobu , Komeda Masashi
Published: September 2004

Background—

Left ventricular aneurysm repair (LVR) reduces LV wall stress and improves LV function. However, as we reported previously, the initial improvement of LVR was short-term because of LV remodeling but could be maintained longer with postoperative use of an angiotensin-converting enzyme (ACE) inhibitor. Atrial natriuretic peptide (ANP) has been used to treat patients with heart failure by natriuretic and vasodilatory actions. Recent reports have suggested that ANP inhibits the rennin-angiotensin system. In this study, the effects of ANP after LVR were evaluated.

Methods and Results—

Rats that had an LV aneurysm 4 weeks after left anterior descending artery ligation underwent LVR by plicating the LV aneurysm and were randomized into 2 groups: LVR+A group was intravenously administrated with 10 μg/h of carperitide, recombinant α-hANP, by osmotic-pump for 4 weeks, and the LVR group was given normal saline. Echocardiography revealed better LV remodeling and function in LVR+A group than in LVR group. Four weeks after LVR, left ventricular end diastolic pressure (LVEDP) and Tau were significantly lower in LVR+A group (LVEDP: 10±4 in LVR+A group versus 18±6 mm Hg in LVR group, Tau: 13±2 versus 17±2ms). End-systolic elastance (Ees) was higher in LVR+A group (Ees: 0.34±0.2 versus 0.19±0.11 mm Hg/μL). The levels of myocardial ACE activity in LVR+A group was significantly lower than in LVR group. The mRNA expressions of brain natriuretic peptide and transforming growth factor β1 inducing fibrosis significantly decreased in LV myocardium in LVR+A group. Histologically, myocardial fibrosis was significantly reduced in LVR+A group.

Conclusions—

Intravenous administration of ANP had beneficial effects on LV remodeling, function, and fibrosis after LVR. ANP could be a useful intravenous infusion drug for postoperative management after LV repair surgery.
Apelin Has In Vivo Inotropic Effects on Normal and Failing Hearts
Authors: Berry Mark F. , Pirolli Timothy J. , Jayasankar Vasant , Burdick Jeffrey , Morine Kevin J. , Gardner Timothy J. , Woo Y. Joseph
Published: September 2004

Background—

Apelin has been shown ex vivo to be a potent cardiac inotrope. This study was undertaken to evaluate the in vivo effects of apelin on cardiac function in native and ischemic cardiomyopathic rat hearts using a novel combination of a perivascular flow probe and a conductance catheter.

Methods and Results—

Native rats (n =32) and rats in heart failure 6 weeks after left anterior descending coronary artery ligation (n =22) underwent median sternotomy with placement of a perivascular flow probe around the ascending aorta and a pressure volume conductance catheter into the left ventricle. Compared with sham-operated rats, the ligated rats had significantly decreased baseline Pmax and max dP/dt. Continuous infusion of apelin at a rate of 0.01 μg/min for 20 minutes significantly increased Pmax and max dP/dt compared with infusion of vehicle alone in both native and failing hearts. Apelin infusion increased cardiac contractility, indicated by a significant increase in stroke volume (SV) without a change in left ventricular end diastolic volume (102±16% change from initial SV versus 26±20% for native animals, and 110±30% versus 26±11% for ligated animals), as well as an increase in preload recruitable stroke work (180±24 mm Hg versus 107±9 mm Hg for native animals).

Conclusions—

The present study is the first to show that apelin has positive inotropic effects in vivo in both normal rat hearts and rat hearts in failure after myocardial infarction. Apelin may have use as an acute inotropic agent in patients with ischemic heart failure.
Aortic Valve Repair Using a Differentiated Surgical Strategy
Authors: Langer Frank , Aicher Diana , Kissinger Anke , Wendler Olaf , Lausberg Henning , Fries Roland , Schäfers Hans-Joachim
Published: September 2004

Background—

Reconstruction of the aortic valve for aortic regurgitation (AR) remains challenging, in part because of not only cusp or root pathology but also a combination of both can be responsible for this valve dysfunction. We have systematically tailored the repair to the individual pathology of cusps and root.

Methods—

Between October 1995 and August 2003, aortic valve repair was performed in 282 of 493 patients undergoing surgery for AR and concomitant disease. Root dilatation was corrected by subcommissural plication (n=59), supracommissural aortic replacement (n=27), root remodeling (n=175), or valve reimplantation within a graft (n=24). Cusp prolapse was corrected by plication of the free margin (n=157) or triangular resection (n =36), cusp defects were closed with a pericardial patch (n=16). Additional procedures were arch replacement (n=114), coronary artery bypass graft (n=60) or mitral repair (n=24). All patients were followed-up (follow-up 99.6% complete), and cumulative follow-up was 8425 patient-months (mean, 33±27 months).

Results—

Eleven patients died in hospital (3.9%). Nine patients underwent reoperation for recurrent AR (3.3%). Actuarial freedom from AR grade ≥II at 5 years was 81% for isolated valve repair, 84% for isolated root replacement, and 94% for combination of both; actuarial freedom from reoperation at 5 years was 93%, 95%, and 98%, respectively. No thromboembolic events occurred, and there was 1 episode of endocarditis 4.5 years postoperatively.

Conclusions—

Aortic valve repair is feasible even for complex mechanisms of AR with a systematic and individually tailored approach. Operative mortality is low and mid-term durability is encouraging. The incidence of valve-related morbidity is low compared with valve replacement.
Alterations in Left Ventricular Torsion and Diastolic Recoil After Myocardial Infarction With and Without Chronic Ischemic Mitral Regurgitation
Authors: Tibayan Frederick A. , Rodriguez Filiberto , Langer Frank , Zasio Mary K. , Bailey Lynn , Liang David , Daughters George T. , Ingels Neil B. , Miller D. Craig
Published: September 2004

Background—

Chronic ischemic mitral regurgitation (CIMR) is associated with heart failure that continues unabated whether the valve is repaired, replaced, or ignored. Altered left ventricular (LV) torsion dynamics, with deleterious effects on transmural gradients of oxygen consumption and diastolic filling, may play a role in the cycle of the failing myocardium. We hypothesized that LV dilatation and perturbations in torsion would be greater in animals in which CIMR developed after inferior myocardial infarction (MI) than in those that it did not.

Methods—

8±2 days after marker placement in sheep, 3-dimensional fluoroscopic marker data (baseline) were obtained before creating inferior MI by snare occlusion. After 7±1 weeks, the animals were restudied (chronic). Inferior MI resulted in CIMR in 11 animals but not in 9 (non-CIMR). End-diastolic septal-lateral and anterior-posterior LV diameters, maximal torsional deformation (φ
max
, rotation of the LV apex with respect to the base), and torsional recoil in early diastole (φ
5%
, first 5% of filling) for each LV free wall region (anterior, lateral, posterior) were measured.

Results—

Both CIMR and non-CIMR animals demonstrated derangement of LV torsion after inferior MI. In contrast to non-CIMR, CIMR animals exhibited greater LV dilation and significant reductions in posterior maximal torsion (6.1±4.3° to 3.9±1.9°* versus 4.4±2.5° to 2.8±2.0°; mean±SD, baseline to chronic, *
P
<0.05) and anterior torsional recoil (−1.4±1.1° to −0.2±1.0° versus −1.2±1.0° to −1.3±1.6°).

Conclusion—

MI associated with CIMR resulted in greater perturbations in torsion and recoil than inferior MI without CIMR. These perturbations may be linked to more LV dilation in CIMR, which possibly reduced the effectiveness of fiber shortening on torsion generation. Altered torsion and recoil may contribute to the “ventricular disease” component of CIMR, with increased gradients of myocardial oxygen consumption and impaired diastolic filling. These abnormalities in regional torsion and recoil may, in part, underlie the “ventricular disease” of CIMR, which may persist despite restoration of mitral competence.
Growth Rate of Aortic Diameter in Patients With Type B Aortic Dissection During the Chronic Phase
Authors: Sueyoshi Eijun , Sakamoto Ichiro , Hayashi Kuniaki , Yamaguchi Tetsuji , Imada Tatuya
Published: September 2004

Background—

The purpose of this study was to evaluate the growth rate of type B double-barrel aortic dissection with computed tomography (CT) and the factors influencing its enlargement.

Methods and Results—

Sixty-two patients were entered into this study, and regular follow-up CT studies (mean; 49.1 months) were performed. The affected aortas and iliac arteries were divided into 5 segments (aortic arch, descending thoracic, suprarenal abdominal, infrarenal abdominal aorta, and iliac artery). Fifty-two of 62 patients (83.9%) had 1 or more segments increased in size during follow-up period. In a total of 177 segments, the presence or absence of blood flow in the false lumen and aortic diameter were evaluated on CT during the follow-up period. The factors (gender, diabetes mellitus, atherosclerotic disease, smoking, entry site in arch, initial diameter, chronic obstructive pulmonary disease, blood pressure, and age) influencing increase in the diameter and growth rate were also evaluated. Of 177 segments, 132 segments (74.6%) increased in size during the follow-up period. The presence of blood flow in the false lumen was the only significant risk factor for increase in the diameter in the univariate and multivariate analysis. The group with blood flow in the false lumen had a significantly higher mean growth rate (3.3 mm/year) than the group without blood flow (−1.4 mm/year) (
P
<0.0001). The growth rate of aortic dissections in thoracic aorta and abdominal aorta were 4.1 and 1.2 mm/year, respectively. There was a significant difference in the growth rate between the 2 groups (
P
=0.0003).

Conclusion—

In type B aortic dissection, the affected aortas have shown a high incidence of enlargement during the follow-up period, and more careful follow-up study is needed for aortic dissections in the thoracic aorta. The presence of blood flow in the false lumen is the most important risk factor for aortic enlargement.
Improvement of Quality of Life After Surgery on the Thoracic Aorta
Authors: Immer Franz F. , Lippeck Christiane , Barmettler Hanna , Berdat Pascal A. , Eckstein Friedrich S. , Kipfer Beat , Saner Hugo , Schmidli Jürg , Carrel Thierry P.
Published: September 2004

Background—

We have recently demonstrated that the use of deep hypothermic circulatory arrest (DHCA) during surgery for acute type A aortic dissections or thoracic aortic aneurysms adversely affect mid-term quality of life (QoL). The aim of this study is to assess the impact of DHCA duration and the potential effects of antegrade cerebral perfusion (ACP) on mid-term QoL.

Methods and Results—

Between January 1994 and December 2002, 363 patients underwent surgery of the thoracic aorta with the use of DHCA at our institution. One hundred seventy-six (48.5%) presented with acute type A dissections and 187 (51.5%) presented with aortic aneurysms. ACP was used in 41 (11.3%) cases. All in-hospital data were assessed and a follow-up was performed in all survivors after 2.4±1.2 years. QoL was analyzed with the Short-Form 36 Health Survey Questionnaire (SF-36). In-hospital mortality was 8.6%. In comparison with patients having undergone DHCA <20 minutes, averaged QoL score was significantly decreased in patients with DHCA between 20 and 34 minutes (95.6±12.8 versus 81.9±15.7;
P
<0.01) and >35 minutes (61.8±18.3;
P
<0.01). Averaged QoL score was significantly better with the use of ACP, independently of the duration of DHCA.

Conclusions—

DHCA duration >20 minutes, and especially >35 minutes, adversely affects mid-term QoL in patients undergoing surgery of the thoracic aorta. The use of ACP, however, improved averaged QoL score at each time period and allows DHCA to be extended up to 30 minutes, without impairment in mid-term QoL.
Role of Interleukin-1β in Acute Inflammation and Graft Death After Cell Transplantation to the Heart
Authors: Suzuki Ken , Murtuza Bari , Beauchamp Jonathan R. , Brand Nigel J. , Barton Paul J. R. , Varela-Carver Anabel , Fukushima Satsuki , Coppen Steven R. , Partridge Terence A. , Yacoub Magdi H.
Published: September 2004

Background—

Poor survival of grafted cells is a major factor hindering the therapeutic effect of cell transplantation; however, the causes of cell death remain unclear. We hypothesized that interleukin-1β (IL-1β) might play a role in the acute inflammatory response and graft death after cell transplantation and that inhibition of IL-1β might improve graft survival.

Methods and Results—

14
C-labeled male skeletal muscle precursor cells were implanted into female mouse hearts by direct intramuscular injection. The amount of
14
C-label provides an estimate of the surviving cell number, whereas the amount of male-specific
Smc
y gene measured by polymerase chain reaction indicates the total (surviving+proliferated) number of donor-derived cells. At 10 minutes after implantation, 44.8±2.4% of the grafted cells survived and this steadily decreased to 14.6±1.1% by 24 hours, and to 7.9±0.6% by 72 hours (n=6 in each point). Proliferation of the surviving cells, which began after 24 hours, resulted in an increase in the total cell number from 15.5±0.8% at 24 hours to 24.4±1.6% at 72 hours. Acute inflammation was prominent at 24 hours and was reduced by 72 hours, in parallel with IL-1β expression. Administration of anti-IL-1β antibody improved graft survival at both 24 (25.6±1.6%) and 72 hours (14.8±1.1%) and resulted in a 2-fold increase in the total cell number at 72 hours (45.8±2.4%). The effects of IL-1β inhibition corresponded with a reduced inflammatory response.

Conclusion—

IL-1β is involved in acute inflammation and graft death after direct intramyocardial cell transplantation. Targeted inhibition of IL-1β may be a useful strategy to improve graft survival.
Suppression of Graft Coronary Artery Disease by a Brief Treatment With a Selective εPKC Activator and a δPKC Inhibitor in Murine Cardiac Allografts
Authors: Tanaka Masashi , Terry Raya D. , Mokhtari Golnaz K. , Inagaki Koichi , Koyanagi Tomoyoshi , Kofidis Theo , Mochly-Rosen Daria , Robbins Robert C.
Published: September 2004

Background—Inhibiting delta protein kinase C (δPKC) during reperfusion and activating epsilon PKC (εPKC) before ischemia each limits cardiac ischemic injury. Here, we examined whether limiting ischemia-reperfusion injury inhibits graft coronary artery disease (GCAD) and improves murine cardiac allografting.

Methods and Results—Hearts of FVB mice (H-2q) were transplanted into C57BL/6 mice (H-2b). εPKC activator (ψεRACK) was injected intraperitoneally (20 nmol) into donor mice 20 minutes before procurement. Hearts were then perfused with ψεRACK (1.5 nmol) through the inferior vena cava (IVC) and subsequently submerged in ψεRACK (0.5 μmol/L) for 20 minutes at 4°C. Before reperfusion, the peritoneal cavity of recipients was irrigated with δPKC inhibitor (δV1-1, 300 nmol); control animals were treated with normal saline. The total ischemic time to the organ was 50 minutes. Two hours after transplantation, production of inflammatory cytokines and adhesion molecules, cardiomyocyte apoptosis, and caspase-3 and caspase-9 (but not caspase-8) activities were significantly reduced in the PKC regulator-treated group. Fas ligand levels (but not Fas) were also significantly reduced in this group. Importantly, GCAD indices, production of inflammatory cytokines, and adhesion molecules were significantly decreased and cardiac allograft function was significantly better as measured up to 30 days after transplantation.

ConclusionsAn εPKC activator and a δPKC inhibitor together reduced GCAD. Clinically, these PKC isozyme regulators may be useful for organ preservation and prevention of ischemia-reperfusion injury and graft coronary artery disease in cardiac transplantation.
Overexpression of Human Copper/Zinc Superoxide Dismutase (SOD1) Suppresses Ischemia–Reperfusion Injury and Subsequent Development of Graft Coronary Artery Disease in Murine Cardiac Grafts
Authors: Tanaka Masashi , Mokhtari Golnaz K. , Terry Raya D. , Balsam Leora B. , Lee Keun-Ho , Kofidis Theo , Tsao Philip S. , Robbins Robert C.
Published: September 2004

Background—

Ischemia–reperfusion injury is an important risk factor for graft coronary artery disease (GCAD). We hypothesized that overexpression of SOD1 in donor hearts would suppress ischemia—reperfusion injury and thereby reduce GCAD.

Methods and Results—

In one series, donor hearts of C57BL/6 (H-2
b
) transgenic mice overexpressing human SOD1 or C57BL/6 wild-type mice were heterotopically transplanted into C57BL/6 recipients and procured after 4 hours of reperfusion (n=6 each). Superoxide, TNF-α, and MCP-1/CCL2 production were significantly reduced in the SOD1 transgenic donor heart recipients, and graft injury determined by serum CPK-MB levels was significantly decreased. Cardiomyocyte apoptosis and caspase-3 and caspase-9 activities were significantly decreased in these recipients; caspase-8 activity was unchanged. Fas ligand but not Fas expression was also reduced. In a second series, transgenic and wild-type hearts were transplanted into C-H-2
bm12
KhEg (H-2
bm12
) recipients, and then procured on day 56 (n=7 each). Cardiac graft beating was significantly better in the SOD1 transgenic donor heart recipients on days 28, 42, and 56 (but not day 14). Significant reduction in luminal narrowing, the intima/media ratio, and the percentage of diseased vessels was seen in the SOD1 transgenic donor heart recipients, and MCP-1/CCL2, ICAM-1, and VCAM-1 production were significantly reduced.

Conclusions—

Overexpression of SOD1 attenuates both apoptosis and the inflammatory response during ischemia—reperfusion injury and therefore mitigates against the subsequent development of GCAD.
Magnetic Vascular Port in Minimally Invasive Direct Coronary Artery Bypass Grafting
Authors: Klima Uwe , MacVaugh Horace , Bagaev Eric , Maringka Michael , Kirschner S. , Beilner J. , Haverich Axel
Published: September 2004

Background—

Minimally invasive direct coronary artery bypass grafting (MIDCAB) is a well-established operative procedure. However, it is technically demanding and is therefore somewhat underused. We evaluated the clinical and angiographic outcome of patients undergoing a MIDCAB procedure with the Ventrica Magnetic Vascular Port (MVP®) system.

Methods and Results—

A Ventrica MVP® system was used in 10 of 11 selected MIDCAB patients. The system consists of 6 magnetic clips, with 3 clips forming a set. One magnetic clip set is positioned at the arteriotomy of the target artery and of the bypass graft using a preloaded delivery system. These ports then form an anastomosis by magnetic coupling. The mean age of the 10 patients (6 male) was 60.3±11.0 years. Three patients had an angiogram at the time of discharge and 8 returned for a 6-month angiogram. The total procedure time was 128.2±12.2 minutes. The mean anastomotic time was 199 seconds. The mean ischemic time during the anastomosis was 146±146 seconds. There were no in-hospital complications and no device-related adverse events. All 3 predischarge and all 8 6-month angiograms showed patent anastomoses.

Conclusions—

The magnetic vascular port facilitates the MIDCAB procedure significantly and reduces the ischemic time during the anastomosis. This minimally invasive procedure has the potential to be an alternative to percutaneous transluminal coronary angioplasty and stenting in proximal left anterior descending (LAD) stenosis. It may expand the acceptance of hybrid procedures in which a left internal mammary artery (LIMA)-to-LAD graft optimally supplies the anterior wall and the septum while the circumflex and right coronary artery may be treated interventionally.
Long-Term Predictors of Aortic Root Dilation and Aortic Regurgitation After Arterial Switch Operation
Authors: Schwartz Marcy L. , Gauvreau Kimberlee , del Nido Pedro , Mayer John E. , Colan Steven D.
Published: September 2004

Background—

Neo-aortic root dilation (ARD) and neo-aortic regurgitation (AR) may be progressive after arterial switch operation (ASO) for d-loop transposition of the great arteries (dTGA). We sought to identify predictors of ARD and AR after ASO.

Methods and Results—

335 patients were identified who underwent ASO for dTGA with intact ventricular septum or ventricular septal defect (VSD), including double-outlet right ventricle (DORV), before 2001 with at least 1 postoperative echocardiogram at our institution, at least 1 year after ASO, and no previous atrial switch procedure (median follow-up of 5.0 years). Probability of freedom from ARD was 97%, 92%, 82%, and 51%, from at least moderate AR was 98%, 97%, 96%, and 93%, and from neo-aortic valve or root surgery was 100%, 100%, 99%, and 95%, at 1, 2, 5, and 10 years, respectively. For patients in whom ARD developed, progressive dilation was not observed during late follow-up. By Kaplan–Meier method, independent predictors of ARD, with neo-aortic root z-score of ≥3.0, were previous pulmonary artery band (PAB) (
P
=0.002, hazard ratio [HR]=2.4) and later time period when ASO was performed (
P
<0.002, HR=19.0). Risk factor for at least moderate AR was age ≥1 year at ASO (
P
=0.002, HR=5.8), which was closely related to VSD repair at ASO (
P
<0.001) and previous PAB.

Conclusions—

Significant ARD and AR continue to develop over time after ASO, but ARD does not tend to be progressive during late follow-up. Previous PAB was a significant risk factor for ARD. Older age at time of ASO, presence of VSD, and previous PAB were risk factors for AR.
Undersized Mitral Annuloplasty Alters Left Ventricular Shape During Acute Ischemic Mitral Regurgitation
Authors: Tibayan Frederick A. , Rodriguez Filiberto , Langer Frank , Liang David , Daughters George T. , Ingels Neil B. , Miller D. Craig
Published: September 2004

Background—

Underlying left ventricular (LV) dysfunction contributes to poor survival after operation to correct ischemic mitral regurgitation (IMR). Many surgeons do not appreciate that a key component of the Bolling undersized mitral ring annuloplasty concept is to decrease LV wall stress by altering LV shape, but precise 3-dimensional (3-D) geometric data do not exist substantiating this effect. We tested the hypothesis that annular reduction decreases regional circumferential LV radius of curvature (ROC) in a model of acute IMR.

Methods—

Eight adult sheep underwent insertion of an adjustable Paneth-type annuloplasty suture and radiopaque markers on the LV and mitral annulus. The animals were studied with biplane videofluoroscopy during baseline conditions, then before and after tightening the annuloplasty suture during proximal left circumflex occlusion. End-systolic circumferential regional LV ROC and mitral annular area were computed.

Results—

Acute IMR was eliminated (MR grade 2.1±0.4 to 0.4±0.4, mean±SD,
P
<0.05) by tightening the Paneth annuloplasty suture. Paneth suture tightening during circumflex occlusion also decreased end-systolic regional circumferential radii of curvature at the basal (anterior, 3.40±0.16 to 3.34±0.14 cm; posterior, 3.31±0.23 to 3.24±0.26 cm;
P
<0.05) and equatorial levels (anterior, 2.99±0.21 to 2.89±0.29 cm; posterior, 2.86±0.38 to 2.81±0.41 cm;
P
<0.05).

Conclusions—

Acute proximal circumflex occlusion caused IMR and increased end-systolic LV radii of curvature in this experimental preparation. Annular reduction sufficient to abolish IMR also decreased end-systolic anterior and posterior LV ROC, which would be expected to reduce LV wall stress and oxygen consumption in these regions, both potentially beneficial effects. The long-term effects of undersized annuloplasty on LV remodeling and function, however, will require further study in chronic animal preparations or patients with chronic IMR.
Cutting Second-Order Chords Does Not Prevent Acute Ischemic Mitral Regurgitation
Authors: Rodriguez Filiberto , Langer Frank , Harrington Katherine B. , Tibayan Frederick A. , Zasio Mary K. , Liang David , Daughters George T. , Ingels Neil B. , Miller D. Craig
Published: September 2004

Background—

Cutting anterior mitral leaflet second-order chordae has been proposed for repair in ischemic mitral regurgitation (IMR). We examined the efficacy of such chordal cutting in preventing acute IMR.

Methods and Results—

Six sheep underwent radiopaque marker placement (left ventricle, mitral annulus, papillary muscles [PMs], and leaflets). The largest second-order chord from each PM was encircled with exteriorized wire snares. Three-dimensional marker coordinates were obtained with biplane videofluoroscopy before and during acute ischemia (80 seconds of mid-circumflex occlusion). Color Doppler transesophageal echocardiography was used to grade MR on a 0 to 4+ scale. Data were acquired immediately before and after dividing second-order chordae. Slope of the end-diastolic volume–stroke work relationship (PRSW) was calculated to assess systolic function. Chordal cutting increased anterior leaflet inflection angle (155±12 versus 162±9 degrees;
P
=0.03), resulting in a flatter leaflet, but did not increase effective leaflet length (1.97±0.24 versus 2.08±0.23 cm;
P
=0.15); PRSW decreased (63±15 versus 56±12 mm Hg;
P
=0.008). Both before and after chordal cutting, ischemia caused: Septal–lateral annular dilation (
P
=0.005), posterior PM displacement away from the mid-septal annulus (
P
=0.06), increased leaflet tenting area (
P
=0.001), and increased leaflet tenting volume (
P
=0.002). Before chordal cutting, MR increased significantly during ischemia (0.5±0.3 versus 1.7±0.4;
P
<0.001), and IMR increased similarly even after the second-order chords were cut (0.7±0.4 versus 1.9±0.9;
P
<0.001).

Conclusions—

Cutting second-order chordae resulted in LV systolic dysfunction and neither prevented nor decreased the severity of acute IMR, septal–lateral annular dilation, leaflet tenting area, or leaflet tenting volume.
Pulmonary Regurgitation Is an Important Determinant of Right Ventricular Contractile Dysfunction in Patients With Surgically Repaired Tetralogy of Fallot
Authors: Frigiola A. , Redington A.N. , Cullen S. , Vogel M.
Published: September 2004

Background—

Evaluation of right ventricular (RV) function in patients with pulmonary regurgitation (PR) after tetralogy repair remains challenging because of abnormal RV loading conditions.

Methods and Results—

We examined 124 patients, aged 21±11.4 years, who had tetralogy repair at 3.7±3.5 years. By Doppler echocardiography, 33 patients had mild, 22 moderate, and 69 severe PR; 55 had significant tricuspid regurgitation (TR). Myocardial velocities, myocardial acceleration during isovolumic contraction (IVA), strain, and strain rate were measured at RV and LV base. Tricuspid valve annulus was measured in a 4-chamber view. QRS, QT, and JT intervals and their dispersions were measured from 12-lead electrocardiogram. IVA in the RV was lower in all patients compared with controls (0.8±0.4 versus 1.8±0.5,
P
<0.0001) and correlated with the severity of PR (
r
=−0.43,
P
<0.0001), whereas myocardial velocities, and strain/strain rate did not. LV IVA correlated with PR (
r
=−0.32,
P
<0.001) and with RV IVA (
r
=0.28,
P
<0.003). Patients with severe PR had a higher incidence of TR (
r
=0.69,
P
<0.0001) and lower RV IVA (1.0±0.4 versus 0.6±0.3,
P
<0.0001), a larger tricuspid valve ring diameter (
P
<0.0001), and prolonged electrical depolarization (
P
<0.001). Age at surgery or examination did not correlate with PR and with RV function assessed by IVA. In the RV, IVA correlated inversely with QRS duration (
P
<0.01).

Conclusions—

Although load-dependent myocardial velocities and strain are not influenced by the severity of PR and presence of significant TR, IVA demonstrates reduced contractile function in relation to the degree of PR and may be an early, sensitive index for selecting patients for valve replacement.
Improved Exercise Capacity and Ischemia 6 and 12 Months After Transendocardial Injection of Autologous Bone Marrow Mononuclear Cells for Ischemic Cardiomyopathy
Authors: Perin Emerson C. , Dohmann Hans F.R. , Borojevic Radovan , Silva Suzana A. , Sousa Andre L.S. , Silva Guilherme V. , Mesquita Claudio T. , Belém Luciano , Vaughn William K. , Rangel Fernando O.D. , Assad Joao A.R. , Carvalho Antonio C. , Branco Rodrigo V.C. , Rossi Maria I.D. , Dohmann Hans J.F. , Willerson James T.
Published: September 2004

Background—

We recently reported the safety and feasibility of autologous bone marrow mononuclear cell (ABMMNC) injection into areas of ischemic myocardium in patients with end-stage ischemic cardiomyopathy. The present study evaluated the safety and efficacy of this therapy at 6- and 12-month follow-up.

Methods and Results—

Twenty patients with 6- and 12-month follow-up (11 treated subjects; 9 controls) were enrolled in this prospective, nonrandomized, open-label study. Complete clinical and laboratory evaluations as well as exercise stress (ramp treadmill), 2-dimensional Doppler echocardiography, single-photon emission computed tomography (SPECT) perfusion scanning, and 24-hour Holter monitoring were performed at baseline and follow-up. Transendocardial delivery of ABMMNCs was performed with the aid of electromechanical mapping to identify viable myocardium. Each patient received 15 ABMMNC injections of 0.2 mL each. At 6 and 12 months, total reversible defect, as measured by SPECT perfusion scanning, was significantly reduced in the treatment group as compared with the control group. At 12 months, exercise capacity was significantly improved in the treatment group. This improvement correlated well with monocyte, B-cell, hematopoietic progenitor cell, and early hemapoietic progenitor cell phenotypes.

Conclusions—

The 6- and 12-month follow-up data in this study suggest that transendocardial injection of ABMMNCs in patients with end-stage ischemic heart disease may produce a durable therapeutic effect and improve myocardial perfusion and exercise capacity.
Prevention of Early Sudden Circulatory Collapse After the Norwood Operation
Authors: De Oliveira Nilto C. , Ashburn David A. , Khalid Faizah , Burkhart Harold M. , Adatia Ian T. , Holtby Helen M. , Williams William G. , Van Arsdell Glen S.
Published: September 2004

Background—

After modifications in our perioperative management protocol, we have observed a decrease in sudden circulatory collapse after the Norwood operation. The current study examines early outcomes after the Norwood operation in our unit in an attempt to identify variables that may have altered the risk of unexpected circulatory collapse.

Methods and Results—

We studied 105 consecutive neonates who underwent a Norwood operation in our institution. Our treatment protocol has changed in the past 3 years to include the use of alpha-blockade with phenoxybenzamine (POB) for systemic afterload reduction and selective cerebral perfusion. Forty-eight infants had selective cerebral perfusion. Forty-two infants received POB. Sixty patients had hypoplastic left heart syndrome. There was no difference in age, diagnosis, number of neonates with weight <2.5 kg, aortic size diameter <2 mm, highest preoperative lactate level, and shunt size indexed to body weight among patients with or without use of POB. Twenty-five infants had circulatory collapse during the first 72 hours. Twelve of them could be explained by technical issues. Thirteen others who appeared clinically stable had early sudden circulatory collapse without an apparent cause. Sixteen out of 25 neonates died. Of those with technical problems, 8 out of 12 died. Based on the hazard function, 3 incremental risk factors for early circulatory collapse were technical issue at operation (
P
<0.001), longer cross-clamp time (
P
<0.007), and no use of POB (
P
<0.002). For a technically successful operation, freedom from circulatory collapse at 72 hours is 95% with the use of POB versus 69% without (
P
<0.002). Diagnosis, aortic size, atrioventricular valve function, birth weight, age at operation, and total circulatory arrest time and were not predictive of early sudden circulatory collapse.

Conclusion—

Recent changes in our treatment protocol have resulted in a decrease incidence of sudden circulatory collapse after the Norwood operation. Optimal surgical technique is the most important predictor of early survival. The use of aggressive afterload reduction with POB reduced the risk of early sudden arrest.
Importance of Mitral Valve Second-Order Chordae for Left Ventricular Geometry, Wall Thickening Mechanics, and Global Systolic Function
Authors: Rodriguez Filiberto , Langer Frank , Harrington Katherine B. , Tibayan Frederick A. , Zasio Mary K. , Cheng Allen , Liang David , Daughters George T. , Covell James W. , Criscione John C. , Ingels Neil B. , Miller D. Craig
Published: September 2004

Background—

Mitral valvular–ventricular continuity is important for left ventricular (LV) systolic function, but the specific contributions of the anterior leaflet second-order “strut” chordae are unknown.

Methods and Results—

Eight sheep had radiopaque markers implanted to silhouette the LV, annulus, and papillary muscles (PMs); 3 transmural bead columns were inserted into the mid-lateral wall between the PMs. The strut chordae were encircled with exteriorized wire snares. Three-dimensional marker images and hemodynamic data were acquired before and after chordal cutting. Preload recruitable stroke work (PRSW) and end-systolic elastance (E
es
) were calculated to assess global LV systolic function (n=7). Transmural strains were measured from bead displacements (n=4). Chordal cutting caused global LV dysfunction: E
es
(1.48±1.12 versus 0.98±1.30 mm Hg/mL,
P
=0.04) and PRSW (69±16 versus 60±15 mm Hg,
P
=0.03) decreased. Although heart rate and time from ED to ES were unchanged, time of mid-ejection was delayed (125±18 versus 136±19 ms,
P
=0.01). Globally, the LV apex and posterior PM tip were displaced away from the fibrous annulus and LV base-apex length increased at end-diastole and end-systole (all +1 mm,
P
<0.05). Locally, subendocardial end-diastolic strains occurred: Longitudinal strain (
E

22

) 0.030±0.013 and radial thickening (
E

33

) 0.081±0.041 (both
P
<0.05 versus zero). Subendocardial systolic shear strains were also perturbed: Circumferential-longitudinal “micro-torsion” (
E

12

) (0.099±0.035 versus 0.075±0.025) and circumferential radial shear (
E

13

) (0.084±0.023 versus 0.039±0.008, both
P
<0.05).

Conclusion—

Cutting second-order chords altered LV geometry, remodeled the myocardium between the PMs, perturbed local systolic strain patterns affecting micro-torsion and wall-thickening, and caused global systolic dysfunction, demonstrating the importance of these chordae for LV structure and function.
Selective Antegrade Cerebral Perfusion Attenuates Brain Metabolic Deficit in Aortic Arch Surgery
Authors: Harrington D.K. , Walker A.S. , Kaukuntla H. , Bracewell R.M. , Clutton-Brock T.H. , Faroqui M. , Pagano D. , Bonser R.S.
Published: September 2004

Background—

Aortic arch surgery has a high incidence of brain injury. This may in part be caused by a cerebral metabolic deficit observed after hypothermic circulatory arrest (HCA). We hypothesized that selective antegrade cerebral perfusion (SACP) would attenuate this phenomenon.

Methods and Results—

In a prospective randomized trial, 42 adult patients were allocated to either HCA (22) or SACP. HCA occurred at a nasopharyngeal temperature of 15°C and SACP at a corporeal temperature of 25°C with cerebral perfusion at 15°C. Paired arterial and jugular venous samples were taken before and after arrest. Continuous transcranial Doppler monitoring of middle cerebral artery velocity (MCAV) was performed. Neuropsychometric testing was performed preoperatively and at 6 and 12 weeks postoperatively. There were 3 hospital deaths (7.1%), 2 strokes (4.8%), and 6 episodes of transient neurological deficit (14.3%). From before to after arrest, jugular bulb pO
2
changed by −21.67 mm Hg (26.4) in the HCA group versus +2.27 mm Hg (18.8) in the SACP group (
P
=0.007). Oxygen extraction changed by +1.7 mL/dL (1.3) in the HCA group versus −1 mL/dL (2.4) in the SACP group (
P
<0.001). MCAV increased by 6.25 cm/s (9.1) in the HCA group and 19.2 cm/s (10.1) in the SACP group (
P
=0.001). Incidence of neuropsychometric deficit at 6 weeks was 6/12 (50%) in HCA patients and 8/10 (80%) in SACP patients (
P
=0.2), and at 12 weeks was 6/16 (38%) in HCA patients and 4/11 (36%) in SACP patients (
P
=1).

Conclusions—

SACP attenuates the metabolic changes seen after HCA. Further studies are required to assess optimal perfusion conditions and clinical outcome.
Inhibition of Matrix Metalloproteinase Activity by TIMP-1 Gene Transfer Effectively Treats Ischemic Cardiomyopathy
Authors: Jayasankar Vasant , Woo Y. Joseph , Bish Lawrence T. , Pirolli Timothy J. , Berry Mark F. , Burdick Jeffrey , Bhalla Ramesh C. , Sharma Ram V. , Gardner Timothy J. , Sweeney H. Lee
Published: September 2004

Background—

Enhanced activity of matrix metalloproteinases (MMPs) has been associated with extracellular matrix degradation and ischemic heart failure in animal models and human patients. This study evaluated the effects of MMP inhibition by gene transfer of TIMP-1 in a rat model of ischemic cardiomyopathy.

Methods and Results—

Rats underwent ligation of the left anterior descending coronary artery with direct intramyocardial injection of replication-deficient adenovirus encoding TIMP-1 (n=8) or null virus as control vector (n=8), and animals were analyzed after 6 weeks. Both systolic and diastolic cardiac function was significantly preserved in the TIMP-1 group compared with control animals (maximum left ventricular [LV] pressure: TIMP-1 70±10 versus control 56±12 mmHg,
P
<0.05; maximum dP/dt 2697±842 versus 1622±527 mmHg/sec,
P
<0.01; minimum dP/dt −2900±917 versus −1195±593,
P
<0.001). Ventricular geometry was significantly preserved in the TIMP-1 group (LV diameter 13.0±0.7 versus control 14.4±0.4 mm,
P
<0.001; border-zone wall thickness 1.59±0.11 versus control 1.28±0.19 mm,
P
<0.05), and this was associated with a reduction in myocardial fibrosis (2.36±0.87 versus control 3.89±1.79 μg hydroxyproline/mg tissue,
P
<0.05). MMP activity was reduced in the TIMP-1 animals (1.5±0.9 versus control 43.1±14.9 ng of MMP-1 activity,
P
<0.05).

Conclusions—

TIMP-1 gene transfer inhibits MMP activity and preserves cardiac function and geometry in ischemic cardiomyopathy. The reduction in myocardial fibrosis may be primarily responsible for the improved diastolic function in treated animals. TIMP-1 overexpression is a promising therapeutic target for continued investigation.
Prospectively Randomized Evaluation of Stented Xenograft Hemodynamic Function in the Aortic Position
Authors: Walther Thomas , Lehmann Sven , Falk Volkmar , Metz Sebastian , Doll Nicolas , Rastan Ardawan , Viehweg Marika , Richter Markus , Gummert Jan , Mohr Friedrich W.
Published: September 2004

Background—

Standard stented aortic xenograft valves have not yet been compared regarding their hemodynamic function using a stratified intraoperative randomization protocol.

Methods and Results—

100 patients were prospectively included after intraoperative metric sizing of the decalcified aortic annulus. They received Mosaic (M) or Perimount (P) aortic valve replacement. Patient age was 73±5 years, 51 were female, and New York Heart Association (NYHA) functional class was 2.8±0.5. The 21-mm annulus group consisted of 5 (M)/7 (P) patients, the 23-mm annulus group of 20 (M)/20 (P), the 25-mm annulus group of 18 (M)/19 (P), and the 27-mm annulus group of 4 (M)/7 (P) patients, respectively. Hemodynamic function was evaluated using transthoracic echocardiography before discharge and at follow-up (438±352 days). Surgery was uncomplicated in all patients. Labeled valve sizes were 0.93 (M) and 1.05 (P) mm smaller than the annulus diameters (
p
=NS). In-hospital mortality was 5%, all nonvalve-related. Transvalvular blood flow velocities and transvalvular pressure gradients were significantly lower in the 25 P versus the 25 M group at baseline and in the 23 P and 25 P groups at follow-up. There was a significant regression of left ventricular mass index in all patients at follow-up. However, left ventricular mass regression was more pronounced after P aortic valve replacement.

Conclusion—

Labeled sizes of prosthetic heart valves implanted are smaller than the true aortic annulus. Both standard aortic xenografts compared in this prospectively randomized trial provide a sufficient hemodynamic and functional outcome.