tbuckley/cabot-search huggingface dataset:
Isometric exercise in patients with chronic advanced heart failure: hemodynamic and neurohumoral evaluation.
Authors: UElkayam, ARoth, LWeber, WHsueh, MNanna, LFreidenberger, P AChandraratna, S HRahimtoola
Journal: Circulation (1985)

We evaluated the hemodynamic effects of isometric exercise in 53 patients with congestive heart failure (CHF) and compared them with those found in 10 normal subjects. In both groups, isometric exercise increased heart rate and blood pressure. Systemic resistance increased in patients with CHF (1862 +/- 520 vs 2126 +/- 642 dyne-sec-cm-5; p less than .001) but not in normal subjects (1359 +/- 268 vs 1380 +/- 252 dyne-sec-cm-5). Cardiac index and stroke volume index increased mildly but not significantly in the normal subjects (2.8 +/- 0.5 vs 3.1 +/- 0.7 liters/min/m2 and 46 +/- 8 vs 47 +/- 7 ml/m2) and showed a significant fall in the patients with CHF (2.1 +/- 0.6 to 1.9 +/- 0.6 liters/min/m2, p less than .01 and 23 +/- 7 vs 20 +/- 7 ml/m2, p less than .01). Mean pulmonary arterial wedge pressure increased in patients with CHF from 26 +/- 7 to 30 +/- 8 mm Hg (p less than .001). Although no significant change was found in mean value for stroke work index (21 +/- 9 vs 20 +/- 9 g-m/m2), the individual change...
His-Purkinje responses and refractory periods during atrial extrastimulation in children with heart defects.
Authors: G SWolff, AMehta, DTamer, O LGarcia, A SPickoff, ACasta, P LFerrer, R JSung, HGelband
Journal: Circulation (1981)

During atrial extrastimulation, split His potentials, prolonged His-to-ventricular (H2V2) intervals and block distal to the His bundle deflection were observed in both preoperative and postoperative children with heart defects. His-Purkinje responses and refractoriness were identified in 31 of 78 (40%) pediatric patients (20 of 51 preoperative and 11 of 27 postoperative) during atrial extrastimulation coupled to sinus and/or paced cycle lengths. Split His potentials were found in 14 patients (eight preoperative and six postoperative) and His bundle relative refractory periods ranged from 250--490 msec. Prolonged H2V2 intervals were found in these and in an additional 16 patients (11 preoperative and five postoperative) and the relative refractory period of the His-Purkinje system ranged from 230--500 msec. Block distal to the His deflection occurred in seven patients (five preoperative and two postoperative) and the effective refractory period ranged from 230--510 msec. Split His potentials, long H2V2 int...
Raynaud's Phenomenon
Authors: E. A. Hines
Journal: JAMA (1962)

<h3>To the Editor:—</h3> The contention of Drs. de Takats and Fowler (<i>JAMA</i><b>179</b>:1, Jan. 6) that Raynaud's phenomenon often precedes the other manifestations of collagen disorders by many years is contrary to the experiences reported previously by us (<i>Circulation</i><b>16</b>:1012, 1957). One facet of this study concerned 280 women and girls who had had Raynaud's phenomenon for at least 2 years without other manifestations of systemic disease when they were first examined at the Mayo Clinic. Follow-up study indicated that only 13 (5%) of these patients subsequently developed systemic disease to which the Raynaud's phenomenon could have been related. The mean duration of follow-up for this group was 17 years from the onset of symptoms of Raynaud's phenomenon. While we agree with Drs. de Takats and Fowler that sympathectomy usually fails when Raynaud's phenomenon is secondary to a collagen disease, our data would indicate that this can explain
Premature ventricular complex morphology. A marker for left ventricular structure and function.
Authors: K PMoulton, TMedcalf, RLazzara
Journal: Circulation (1990)

The shape of a premature ventricular complex (PVC) might reflect the presence or absence of myocardial disease. To test this, 100 patients with a PVC on a 12-lead electrocardiogram at cardiac catheterization or nuclear angiography were classified according to PVC morphology. Group 1 (n = 50) had PVC QRS complexes with either smooth and uninterrupted contour or with narrow (less than 40 msec) notching. Group 2 (n = 50) demonstrated PVC with broad (greater than or equal to 40 msec) notching or shelves. Clinical, electrocardiographic and angiographic variables were assessed to define group differences. All patients had one or more etiological forms of heart disease none of which distinguished either group. Groups 1 and 2 differed with respect to a history of congestive heart failure (12% vs. 66%, p = 0.0004), dilated cardiomyopathy (2% vs. 38%, p = 0.0005), and the presence of mitral regurgitation (13% vs. 58%, p = 0.001), respectively. In group 1, 45 of 50 (90%) patients with a PVC had no notching. Patients...
RE: Primary Tumor Location as a Prognostic Factor in Metastatic Colorectal Cancer
Authors: Felice N. van Erning, Marloes A. Elferink, Amanda C. R. K. Bos, Valery E. P. P. Lemmens
Journal: JNCI Journal of the National Cancer Institute (2015)

With interest we read the paper by Loupakis et al. (1), in which the prognostic impact of primary tumor location in metastatic colorectal cancer (CRC) was investigated. They found that patients with left-sided tumors had a lower risk of death and progression as compared with patients with right-sided tumors. We repeated the analyses for metastatic CRC patients and additionally investigated whether survival outcomes are also more favorable for patients with left-sided tumors as compared with right-sided tumors in case of nonmetastatic CRC.
Induction of insulin-like growth factor I messenger RNA in rat aorta after balloon denudation.
Authors: BCercek, M CFishbein, J SForrester, R HHelfant, J AFagin
Journal: Circulation Research (1990)

Insulin-like growth factor I (IGF-I) is a widely distributed mitogen that mediates the growth-promoting effects of platelet-derived growth factor in mesenchymal cells. We show that rat aortic IGF-I messenger RNA (mRNA) is induced 24 hours after deendothelialization, at a time when smooth muscle cell proliferation within the intima is still not apparent. After 7 days, IGF-I mRNA induction peaks at about ninefold control levels and then falls to about threefold 14 days after denudation when smooth muscle cell proliferation is at its peak. We also show that, of the 5' untranslated IGF-I mRNA transcripts, only the class C transcript is expressed and regulated in aortic tissue. In contrast, treatment of rats with supraphysiological doses of growth hormone, the major endocrine regulator of IGF-I gene expression, elicited only twofold induction of aortic IGF-I mRNA. Our findings suggest that IGF-I may be an important autocrine or paracrine regulator of smooth muscle cell proliferation and that it may be signific...
Abstract 9892: Global Metabolomic Profiling Reveals Lower Lysophospholipids Levels in Multiple Myeloma Patients With Carfilzomib-Related Cardiotoxicity
Authors: Yimei Huang, Timothy J Garrett, Lihui Yuan, Michael G Fradley, Robert F Cornell, Rachid C Baz, Chintan P Shah, Taimour Langaee, Nida Waheed, Carl J Pepine, Moreb S Jan, Yan Gong
Journal: Circulation (2019)

Introduction: Carfilzomib, a proteasome inhibitor, has been associated with cardiotoxicities including heart failure (HF) in multiple myeloma (MM) patients. Previous global metabolomic profiling st...
Intravenous nitroglycerin in the treatment of spontaneous angina pectoris: a prospective, randomized trial.
Authors: G DCurfman, J AHeinsimer, E CLozner, H LFung
Journal: Circulation (1983)

A prospective, randomized study of i.v. nitroglycerin (TNG) in the management of repetitive spontaneous angina pectoris was undertaken in 40 consecutive patients. The clinical effectiveness of i.v. TNG (group A) was compared with that of oral isosorbide dinitrate (ISDN) and topical 2% nitroglycerin ointment (NO) in combination (group B) during a 72-hour treatment period. The doses of both nitrate regimens were adjusted so that the mean arterial pressure in the two groups was reduced by 15 +/- 3% of control values to the same level (77 mm Hg). The i.v. TNG dose of 10-200 micrograms/min yielded arterial plasma TNG levels of 1.2-65.3 ng/ml and estimated plasma (arterial) clearance of 106 +/- 55 ml/min/kg of body weight (mean +/- SD). In group B, the doses were 20-60 mg (oral ISDN) and 1/2-2 inches (NO) every 6 hours. Intravenous TNG reduced the number of spontaneous ischemic episodes from 3.3 +/- 0.8 per 24 hours during the control period to 1.0 +/- 0.3 per 24 hours during the treatment period (p less than 0...
Hormone replacement therapy
Authors: M. Hickey, J. Elliott, S. L. Davison
Journal: BMJ (2012)

A 51 year old woman presents to her general practitioner with troublesome hot flushes and night sweats for the past eight months.She is sexually active and her last period was about 5 months ago.She has taken a number of over-the-counter preparations, but none have been effective.She is anxious about having hot flushes at work and exhausted from sleep disturbance.She wants advice about managing her symptoms.
Cardiac involvement in Whipple's disease.
Authors: H AMcAllister, J JFenoglio
Journal: Circulation (1975)

Although cardiac involvement in Whipple's disease has been reported previously, the extent and significance of such involvement has not been stressed. In our series of 19 patients, 58% had clinical cardiac findings and 79% had gross cardiac lesions at autopsy. Histologically there were PAS-positive macrophages in the pericardium, myocardium, and valves of each of these patients. These collections of macrophages were associated with chronic inflammatory cells and foci of fibrosis with resultant adhesive pericarditis, focal myocardial fibrosis similar to the fibrosis of idiopathic cardiomyopathy, and valvular fibrosis with deformity grossly resembling the valvular lesions of chronic rheumatic heart disease. Four of the patients with mitral valvular deformity had cardiac murmurs, and ECG changes were noted in six patients with mitral myocardial fibrosis. In addition, pericardial friction rubs were heard in two patients. By electron microscopy rod-shaped bodies, presumably bacteria, were noted in the mitral v...
Association of Intravenous Radiocontrast With Kidney Function
Authors: Robert Goulden, Brian H. Rowe, Michal Abrahamowicz, Erin Strumpf, Robyn Tamblyn
Journal: JAMA Internal Medicine (2021)

Radiocontrast has long been thought of as nephrotoxic; however, a number of recent observational studies found no evidence of an association between intravenous contrast and kidney injury. Because these studies are at high risk of confounding and selection bias, alternative study designs are required to enable more robust evaluation of this association.To determine whether intravenous radiocontrast exposure is associated with clinically significant long-term kidney impairment, using a study design that permits stronger causal interpretation than existing observational research.This cohort study included all emergency department patients aged 18 years or older undergoing D-dimer testing between 2013 and 2018 in the Canadian province of Alberta. A fuzzy regression discontinuity design was used, exploiting the fact that individuals just either side of the eligibility cutoff for computed tomographic pulmonary angiogram (CTPA)-typically 500 ng/mL-have markedly different probabilities of contrast exposure, but should otherwise be similar with respect to potential confounders.Intravenous contrast in the form of a CTPA.Estimated glomerular filtration rate (eGFR) up to 6 months following the index emergency department visit.During the study period 156 028 individuals received a D-dimer test. The mean age was 53 years, 68 206 (44%) were men and 87 822 (56%) were women, and the mean baseline eGFR level was 86 mL/min/1.73 m2. Patients just above and below the CTPA eligibility cutoff were similar in terms of measured confounders. There was no evidence for an association of contrast with eGFR up to 6 months later, with a mean change in eGFR of -0.4 mL/min/1.73 m2 (95% CI, -4.9 to 4.0) associated with CTPA exposure. There was similarly no evidence for an association with need for kidney replacement therapy (risk difference [RD], 0.07%; 95% CI, -0.47% to 0.61%), mortality (RD, 0.3%; 95% CI, -2.9% to 3.2%), and acute kidney injury (RD, 4.3%; 95% CI, -2.7% to 12.9%), though the latter analysis was limited by missing data. Subgroup analyses were potentially consistent with harm among patients with diabetes (mean eGFR change -6.4 mL/min/1.73 m2; 95% CI, -15.4 to 0.2), but not among those with other reported risk factors for contrast-induced nephropathy; these analyses, however, were relatively underpowered.Using a cohort study design and analysis that permits stronger causal interpretation than existing observational research, we found no evidence for a harmful effect on kidney function of intravenous contrast administered for CTPA in an emergency setting.
Simultaneous echocardiographic phonocardiographic recordings at rest and during amyl nitrite administration in patients with mitral valve prolapse.
Authors: R AWinkle, D JGoodman, R LPopp
Journal: Circulation (1975)

Simultaneous electrocardiograms, phonocardiograms, and echocardiograms were recorded in 21 patients with mitral valve prolapse. Four patients with holosystolic mitral valve prolapse on echocardiogram had smaller resting end-diastolic volumes than the remaining 17 patients with late systolic echocardiopraphy prolapse (p greater than 0.01). Thirteen of the 17 patients with late systolic prolapse had phonocardiograhically recorded auscultatory phenomena. The initial vibrations of the auscultatory phenomena occurred after the onset of echocardiographic prolapse, but prior to maximal echocardiographic mitral valve prolapse. Amyl nitrite was administered to all patients. Three of the 17 patients with late systolic prolapse developed holosystolic prolapse, while the remaining 14 retained the late systolic prolapse pattern during amyl nitrite inhalation. In these 14 patients, the onset of mitral prolapse occurred earlier in systole due to decrease in the duration of systole prior to onset of mitral valve prolapse...
Effect of filming projection and interobserver variability on angiographic biplane left ventricular volume determination.
Authors: W JRogers, L RSmith, W PHood, J AMantle, C ERackley, R ORussell
Journal: Circulation (1979)

Although biplane right anterior oblique-left anterior oblique (RAO/LAO) quantitative left ventricular (LV) angiography is commonly performed, justification of LV volume calculation using the area length method (originally formulated from anteroposterior-lateral (AP/LAT) angiograms) has been limited. To assess whether RAO/LAO and AP/LAT LV volumes are similar when computed by the area length method formula, we performed biplane cine LV angiography in both RAO/LAO and AP/LAT projections in random sequence in 21 patients and four LV models of known volume. LV silhouettes were drawn independently by two trained observers. Calculated angiographic volume of the models correlated almost exactly with their true volume (r = 0.999), establishing the absolute accuracy of this system. Rotation of the LV models through 90 degrees of obliquity at 10 degree increments demonstrated a mean change from true volume of only -5.4 +/- 0.7% (p less than 0.001). In the patient studies, rotation to the 30 degree RAO/60 degree LAO...
Prognostic value and physiological correlates of heart rate variability in chronic severe mitral regurgitation.
Authors: K MStein, J SBorer, CHochreiter, P MOkin, E MHerrold, R BDevereux, PKligfield
Journal: Circulation (1993)

BACKGROUNDA variety of measures of heart rate variability have been devised to measure high-frequency (0.15-0.40 Hz), low-frequency (0.04-0.15 Hz), or ultralow-frequency (< 0.0033 Hz) fluctuations in sinus cycle length. Although measures of low-frequency and ultralow-frequency heart rate variability have been shown to correlate with prognosis in several populations with ischemic heart disease, their relevance to patients with primary valvular heart disease remains to be determined.METHODS AND RESULTSThirty-eight patients with nonischemic causes of chronic severe mitral regurgitation who were in sinus rhythm underwent 24-hour ambulatory electrocardiography as part of a prospective study of the natural history of regurgitant valvular heart disease. Patients were followed for as long as 9.2 years, and end points of mortality, progression to mitral valve surgery, and development of chronic atrial fibrillation were tabulated. Time- and frequency-domain measurements of high-frequency, low-frequency, and ultralo...
Effect of thyroid status on thin-filament Ca2+ regulation and expression of troponin I in perinatal and adult rat hearts.
Authors: L JDieckman, R JSolaro
Journal: Circulation Research (1990)

There is evidence for the existence of developmental changes in expression of troponin I (TNI) in cardiac thin filaments; however, regulation of TNI expression has not been described. We tested whether thyroid state affects expression of TNI using neonatal and adult rats made hypothyroid by treatment with 6-n-propyl-2-thiouracil. Polyacrylamide gels of myofibrils from hearts of 7-, 14-, 21-, and 28-day-old animals indicated that both euthyroid and hypothyroid rats display a developmental shift toward the adult form of TNI. However, hypothyroid rats displayed a lower percentage of adult TNI at each age studied. When adult rats were made hypothyroid, the proportion of adult TNI decreased slightly. Thin-filament activity was determined from measurements of the effect of acidic pH on calcium activation of myofibrillar ATPase activity. Sensitivity to acidic pH was measured by the magnitude of shift in pCa50 (-log of half-maximally activating molar Ca2+) between pH 7.0 and 6.5. Euthyroid rats displayed developm...
Redistribution of collateral blood flow from necrotic to surviving myocardium following coronary occlusion in the dog.
Authors: H OHirzel, G RNelson, E HSonnenblick, E SKirk
Journal: Circulation Research (1976)

Early changes in collateral blood flow after acute coronary occlusion may be critical for survival of ischemic myocardium. We used 15-mum radioactive microspheres to study myocardial blood flow in thoracotomized dogs 10 minutes and 24 hours after occlusion of the left anterior descending coronary artery (LAD). The ischemic area was delineated by dye injected into the distal artery, and indentification of potentially ischemic samples was confirmed by a newly developed technique in which microspheres were excluded from the normally perfused LAD. Layers were separated into necrotic or normal as defined by gross inspection and confirmed by histological examination and creatine phosphokinase assay. Infarction always involved endocardial layers and extended toward the epicardium. Average myocardial blood flow in 48 necrotic samples from 16 dogs either remained low (less than 0.05 ml/min g-1) or declined, falling from 0.11 +/-0.02(SE) at 10 minutes to 0.05 +/-0.01 ml/min g-1 at 24 hours (P less than 0.001). In c...
Effects of synthetic atrial natriuretic peptide on renal function and renin release in acute experimental heart failure.
Authors: T AScriven, J CBurnett
Journal: Circulation (1985)

Studies were performed in anesthetized control dogs (n = 6) and in dogs (n = 6) with acute low-output heart failure produced by inflation of a balloon in the thoracic inferior vena cava. Studies were designed to determine the effects of synthetic atrial natriuretic peptide on renal function and renin release in this acute high-renin, sodium-retaining preparation. Intrarenal infusion of synthetic atrial natriuretic peptide (0.3 micrograms X kg-1 X min-1) resulted in decreases in arterial pressure and renal blood flow in both groups. Glomerular filtration rate increased in both low-output (delta + 10.7 +/- 3.1 ml/min) and control (delta + 8.7 +/- 2.9 ml/min) groups. Fractional lithium excretion, a marker of proximal tubule reabsorption, also increased in both low-output (delta + 12.0 +/- 4.6%) and control (delta + 14.3 +/- 5.0%) groups. Renin secretory rate decreased in the low-output group from 852.8 +/- 183.0 to 149.5 +/- 73.7 ng/min and in the control group from 308.5 +/- 84.5 to 44.5 +/- 27.5 ng/ml. Int...
Regional wall motion analysis predicts survival and functional outcome after subendocardial resection in patients with prior anterior myocardial infarction.
Authors: SNath, D EHaines, I LKron, M JBarber, J PDiMarco
Journal: Circulation (1993)

BACKGROUNDSubendocardial resection is an established surgical technique for the treatment of ventricular tachycardia associated with prior myocardial infarction. Preoperative factors predictive of survival and functional outcome after surgery have not been completely characterized. We hypothesized that a quantitative assessment of regional wall motion would be a sensitive predictor of both survival and functional outcome after subendocardial resection. This was retrospectively tested in a group of 80 patients with prior anterior myocardial infarction who had undergone subendocardial resection for sustained ventricular tachycardia at out institution.METHODS AND RESULTSCenterline chord motion analysis was used to derive a wall motion score from the preoperative contrast right anterior oblique ventriculogram. Multivariate analysis revealed wall motion score to be a significant independent predictor of both long-term survival (p < 0.01) and New York Heart Association (NYHA) functional class I or II status at ...
Hypertrophic cardiomyopathy in infants: clinical features and natural history.
Authors: B JMaron, A JTajik, H DRuttenberg, T PGraham, G FAtwood, B EVictorica, J TLie, W CRoberts
Journal: Circulation (1982)

The clinical and morphologic features of hypertrophic cardiomyopathy in 20 patients recognized as having cardiac disease in the first year of life are described. Fourteen of these 20 infants were initially suspected of having heart disease solely because a heart murmur was identified. However, the infants showed a variety of clinical findings, including signs of marked congestive heart failure (in the presence of non-dilated ventricular cavities and normal or increased left ventricular contractility) and substantial cardiac enlargement on chest radiograph. Other findings were markedly different from those usually present in older children and adults with hypertrophic cardiomyopathy (e.g., right ventricular hypertrophy on the ECG and cyanosis). Consequently, in 14 infants, the initial clinical diagnosis was congenital cardiac malformation other than hypertrophic cardiomyopathy. Twelve of the 14 infants who underwent left-heart catheterization showed substantial obstruction to left ventricular outflow (peak...
Reducing unnecessary red blood cell transfusion in hospitalised patients
Authors: Nishila Mehta, Michael F Murphy, Lawrie Kaplan, Wendy Levinson
Journal: BMJ (2021)

### What you need to know

Transfusion of red blood cells (RBC) is used to treat patients with severe anaemia or bleeding. Supplies of blood for transfusion need to be protected, as countries have experienced a decline in donation rates during the covid-19 pandemic.1 However, published international audits describe inappropriate rates of RBC transfusion of 22-57% in a variety of clinical settings, including hospitalised inpatients, operative units, and emergency departments.234 Unnecessary blood transfusions may expose patients to harms, including allergic, febrile, or haemolytic reactions; circulatory overload associated with transfusion (seen in up to 1-6% of transfused patients); and acute lung injury.5 These complications may occur without the transfusion adding any clinical benefit. Blood products are costly to collect and administer. Their overuse wastes a limited precious resource donated by the public.6

Conservative blood use, often referred to as “restrictive transfusion practice,” is recommended in stable, non-bleeding patients by the National Institute for Health and Care Excellence (NICE) and the Choosing Wisely campaigns in Canada, the UK, and the US.78910 Recommendations focus on two major clinical decision points: the haemoglobin concentration (Hb) at which blood transfusion is considered, and the number of RBC units administered at a time (table 1).

View this table:

Table 1 
When to transfuse RBCs in the adult inpatient78 …