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PubMed1993

Effects of exercise or temporary coronary occlusion during angioplasty on right ventricular function with consideration of left-anterior-descending- and right-coronary-artery-related myocardial ischemia.

Whether exercise causes right ventricular ischemia severe enough to depress right ventricular function is still controversial. Therefore, right ventricular function was evaluated in 44 patients with isolated coronary artery disease of either the proximal left anterior descending or right coronary artery during exercise (n = 22) or balloon occlusion during percutaneous transluminal coronary angioplasty (PTCA) (n = 22). Central hemodynamics and right ventricular volumes were determined using a new thermodilution Swan-Ganz catheter. Exercise increased right ventricular end-diastolic volume index [from 89 (66-127) to 101 (70-130) ml m-2, p = 0.00005; median (range)] and stroke volume index [from 44 (27-68) to 53 (36-75) ml m-2, p = 0.0005]. During PTCA, right ventricular end-diastolic volume index remained unchanged, while stroke volume index decreased from 49 (38-60) to 40 (26-49) ml m-2 (p = 0.00005). The decrease in right ventricular ejection fraction during exercise from 56 (41-64) to 52% (39-64) reached only borderline significance (p = 0.06) and was significantly (p = 0.02) smaller than during angioplasty [from 53 (44-62) to 41% (25-66; p = 0.0008)]. Right ventricular ejection fraction did not differ between left anterior descending or right coronary artery obstruction and did not depend on right ventricular afterload. In comparison to exercise angioplasty caused a decreased systolic pressure-volume ratio and a leftward shift of the diastolic pressure-volume curve. In conclusion, exercise has only little effect on right ventricular ejection fraction, whereas inadequate oxygen supply during balloon angioplasty induces severe depression of right ventricular function.

Adult↗
PubMed1995

Heterogeneity of ventricular function and myocardial oxidative metabolism in nonischemic dilated cardiomyopathy.

OBJECTIVES: This study was performed to test the hypothesis that regional variation in ventricular function in patients with nonischemic dilated cardiomyopathy is related to regional variation in oxidative metabolism. BACKGROUND: Heterogeneity in regional left ventricular function has long been noted in patients with nonischemic dilated cardiomyopathy. Regional variation in wall stress has been proposed as the pathophysiologic mechanism. By correlating regional function with oxidative metabolism, one can test the hypothesis that heterogeneity in wall stress is responsible for heterogeneity in function. We hypothesized that preserved function as a result of more favorable loading conditions would be associated with regional oxidative metabolism that is equal to or lower than that in other regions. METHODS: Fifteen patients with nonischemic dilated cardiomyopathy (mean [+/- SD] ejection fraction 20.7 +/- 4.0%) were studied. Regional ventricular function was determined using short-axis chordal shortening on two-dimensional echocardiography. Regional oxidative metabolism was assessed by carbon-11 acetate clearance kinetics on dynamic positron emission tomography. An eight-segment model of the left ventricle was used. Segmental function and oxidative metabolism were defined as increased if they varied at least 1 SD from the respective mean value for that patient. RESULTS: Thirteen (87%) of 15 patients exhibited segments with increased function. In 7 (54%) of 13 patients, regional function was increased in the proximal lateral wall. Multivariate linear regression analysis showed a direct relation between regional function and oxidative metabolism (p = 0.02). The average concordance between increased function and increased oxidative metabolism among patients was 0.87 +/- 0.11 (95% confidence interval 0.70 to 1.00). CONCLUSIONS: Patients with nonischemic dilated cardiomyopathy display heterogeneity in regional ventricular function. Relative preservation is observed most frequently in the proximal lateral wall. Relative preservation of function is associated with higher regional oxidative metabolism, suggesting that mechanisms other than or in addition to local loading conditions may be responsible for heterogeneity in function.

Acetates↗
PubMed1993

Left ventricular function during exercise after aortic valve replacement.

To evaluate the difference in left ventricular function during exercise after successful aortic valve replacement, left ventricular function was investigated using radionuclide angiography in 12 patients with normal resting left ventricular systolic function. Patients were divided into two groups: Group 1 was comprised of 5 patients after aortic valve replacement for aortic stenosis and group 2 was comprised of 7 patients for aortic insufficiency. Left ventricular ejection fraction increased significantly during exercise in both groups. The increase in systolic arterial pressure to left ventricular end-systolic volume was significantly larger in group 1 than group 2, whereas the increase in left ventricular end-diastolic volume was significantly larger in group 2 than group 1. Thus, increase in left ventricular contractility played an important role in regulating increased left ventricular ejection fraction during exercise in patients with aortic prostheses for aortic stenosis, whereas increase in left ventricular end-diastolic volume played an important role in patients with aortic prostheses for aortic insufficiency.

Adult↗
PubMed1992

The effect of calcium on pulmonary vascular resistance and right ventricular function.

Calcium chloride is frequently administered to patients immediately after separation from cardiopulmonary bypass to improve the contractile state of the myocardium. Animal studies suggest that calcium chloride may produce increases in pulmonary vascular resistance, which can precipitate right ventricular failure. In an attempt to determine the effect of calcium chloride administration after cardiopulmonary bypass on right ventricular function, this study was designed to evaluate patients with normal and elevated pulmonary vascular resistance. Fifty patients scheduled for elective cardiac surgery were prospectively studied for changes in ionized calcium levels before and after bypass. The impact of calcium administration on right ventricular function was assessed by a pulmonary artery catheter modified for the measurement of right ventricular ejection fraction. In all patients the level of ionized calcium decreased during bypass from a mean of 4.91 to 4.29 mg.dl-1. However, the infusion of calcium chloride (10 mg.kg-1) after bypass resulted in increasing the ionized calcium levels to prebypass levels. Administration of calcium chloride after bypass to patients with normal right ventricular function resulted in a transient increase in both cardiac output and right ventricular ejection fraction without any change in pulmonary vascular resistance. Eight patients with both elevated pulmonary vascular resistance and depressed right ventricular function were evaluated to determine the effect of calcium chloride after bypass on pulmonary vascular resistance and right ventricular ejection fraction. Administration of calcium chloride (10 mg.dl-1) to these patients did not result in any significant increase in pulmonary vascular resistance or depression of right ventricular performance. More important, in these patients, right ventricular ejection fraction and cardiac output were significantly increased after calcium chloride administration. In summary, the results of this study fail to demonstrate any increase in pulmonary vascular resistance or deterioration of right ventricular function with the administration of calcium chloride (10 mg.kg-1) after bypass in patients with elevated pulmonary vascular resistance.

Aged↗
PubMed1990

Relation between beta-adrenergic blocker use, various correlates of left ventricular function and the chance of developing congestive heart failure. The Multicenter Diltiazem Post-Infarction Research Group.

This study examined the relations among beta-adrenergic blocker use, various correlates of left ventricular function and the chance of developing congestive heart failure in patients after myocardial infarction. The study was performed with the placebo group of the Multicenter Diltiazem Post-Infarction Trial. Ejection fraction data were available in 1,084 patients; of these, 557 were receiving a beta-blocker and 527 were not. In addition to ejection fraction, other correlates of left ventricular function included the presence or absence of pulmonary rales, chest X-ray film evidence of pulmonary congestion and the presence of an S3 gallop. Beta-blocker use was less frequent in patients with an ejection fraction less than 30%, rales, an S3 gallop and pulmonary congestion on chest X-ray film. Twenty-one percent of patients with an ejection fraction less than 30%, 42% of patients with rales, 28% of patients with an S3 gallop and 28% of patients with pulmonary congestion were receiving beta-blocker therapy. For every correlate of left ventricular function, the chance of developing congestive heart failure was greater in patients with diminished left ventricular function than in those without. For each level of left ventricular function, the chance of developing congestive heart failure requiring treatment was greater in patients not taking a beta-blocker.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗
PubMed1988

Relation between histological findings on early repeat right ventricular biopsy and ventricular function in patients with myocarditis.

Histological findings on repeat endomyocardial biopsy and changes in left ventricular ejection fraction early during immunosuppressive treatment were studied in 20 patients with documented myocarditis. All patients presented with heart failure of less than six months' duration and a left ventricular ejection fraction of less than or equal to 0.40. Repeat biopsy and assessment of ventricular function were performed at a mean (SEM) of 79 (17) days after the initial biopsy. At repeat biopsy eight patients had evidence of ongoing myocarditis and 12 showed resolved myocarditis. In eight (66%) of the 12 patients with resolved myocarditis ventricular function had improved significantly. Left ventricular ejection fraction also improved significantly in four of eight patients during treatment despite ongoing myocardial inflammation. Regardless of the histological findings on repeat biopsy, early improvement in ejection fraction was associated with an excellent long term prognosis--that is 83% survived for at least three years. Histological resolution of myocarditis during immunosuppressive treatment is not a prerequisite for improvement in ventricular function; and changes in left ventricular ejection fraction during the first three months of treatment are predictive of clinical outcome.

Adult↗
PubMed2005

Isolated mitral valve repair in patients with depressed left ventricular function.

BACKGROUND: The utility of mitral valve repair (MV repair) has been well documented in patients with normal left ventricular function. Few studies, however, have specifically examined outcomes of isolated MV repair in patients with decreased left ventricular function. The purpose of the present study is to review a modern experience with isolated MV repair in patients with depressed left ventricular function and to examine intermediate outcomes. METHODS: A retrospective review of patients who underwent MV repair from 1996 to 2003 was performed to identify consecutive patients who had isolated MV repair. Preoperative studies were reviewed to further identify patients with an ejection fraction less than 0.45. Clinical operative data were collected from the medical record, and survival was determined with the Social Security Death Index. Further end points of reoperation and transplantation were also noted. RESULTS: A total of 101 patients were identified with a mean follow-up of 1,124 days. Mean ejection fraction and age was 0.34 +/- 0.09 and 56 +/- 14 years, respectively. Thirty-day mortality was 2.9%. One- and 5-year survival was 94% +/- 2% and 70% +/- 6%, respectively. There was no statistically significant difference in actuarial survival for functional versus primary mitral disease, or for ejection fraction less than 0.35 versus greater than 0.35. Six patients required transplantation. Five-year freedom from reoperation, transplantation, and death was 61% +/- 11% and 54% +/- 8% for patients with primary and secondary mitral valve disease, respectively (p = 0.279). Minimally invasive MV repair was performed in 57 patients with a mean ejection fraction of 0.369 +/- 0.07 and a 30-day mortality of 1.7%. CONCLUSIONS: In patients with isolated MV regurgitation and depressed left ventricular function, MV repair can be achieved with low operative mortality, but there remains a persistent risk of death, reoperation, or transplantation irrespective of valve disease. Minimally invasive MV repair was safe in this group.

Cardiac Surgical Procedures↗
PubMed2005

Evaluation of right ventricular function in patients with thyroid dysfunction.

BACKGROUND: Thyroid gland dysfunction affects the structure and function of the heart. Tissue Doppler echocardiography is a new technique, and it has been used frequently in the evaluation of ventricular function. In the present study, right ventricular function was assessed in patients with overt or subclinical hypothyroidism and hyperthyroidism and in healthy subjects using the tissue Doppler method, and results were compared. PATIENTS AND METHODS: 20 healthy subjects and 63 patients diagnosed with overt and subclinical hypothyroidism and hyperthyroidism were included in the study. Annular and myocardial systolic peak velocities, early and late diastolic peak velocities, precontraction, total contraction and relaxation times of the right ventricle were recorded by tissue Doppler echocardiography. The results of the patients were compared to those of the controls. RESULTS: Myocardial systolic velocity was significantly higher in patients with hyperthyroidism. Annular and myocardial late diastolic velocities were found to be significantly lower in patients with overt hypothyroidism. Annular precontraction time was increased in patients with overt and subclinical hypothyroidism. Myocardial precontraction time was decreased in patients with hyperthyroidism, and increased in patients with overt hypothyroidism patients. Annular relaxation time was increased in patients with overt hypothyroidism. CONCLUSIONS: Right ventricular function is affected in patients with thyroid diseases. The tissue Doppler technique is a suitable tool to detect impairments in right ventricular function. There is a significant correlation between serum thyroid hormone levels and right ventricular velocities and time intervals.

Adult↗
PubMedDate not supplied

Effects of dipyridamole on left ventricular function.

BACKGROUND: Changes induced by dipyridamole infusion on left ventricular function in healthy individuals have not been investigated by gated myocardial perfusion single photon emission computed tomographic (SPECT) imaging. METHODS AND RESULTS: This study examined the amplitude and duration of changes induced by dipyridamole infusion on left ventricular function as assessed by technetium 99m sestamibi gated SPECT in 18 subjects with a low likelihood of coronary artery disease. Twenty mCi (740 MBq) of Tc-99m sestamibi were injected at rest. Three different consecutive gated SPECT images were performed 60 minutes later: baseline at rest, during the infusion of 0.76 mg/kg of dipyridamole, and 1 hour later. No patient received aminophylline. Left ventricular ejection fraction (LVEF), end-diastolic volume, and end-systolic volume were automically computed. Heart rate (HR) and blood pressure were regularly monitored. Mean LVEF was 63.2% +/- 8.0% baseline at rest, increased to 73.8% +/- 8.2% (P = .0001) during dipyridamole infusion, and returned to baseline values (63.0% +/- 7.5%) 1 hour later. End-diastolic volume did not vary significantly, and end-systolic volume decreased (from 32.2 +/- 19.5 to 26.6 +/- 17.9 u, P = .002) and returned to baseline values (32.7 +/- 15.6 u) 1 hour later. Dipyridamole induced moderate HR acceleration (from 80.2 +/- 15.0 to 96.5 +/- 9.6 beats/min, P < .001) and a slight decrease in diastolic blood pressure (from 80.6 +/- 8.1 to 70.1 +/- 9.0 mm Hg, P < .001). However, 1 hour later, HR and blood pressure had returned to baseline values. CONCLUSIONS: Dipyridamole increases LVEF and HR and decreases diastolic blood pressure slightly in healthy individuals. Because dipyridamole gated SPECT imaging acquisition is usually started 60 minutes after dipyridamole infusion, LVEF is in fact estimated at rest.

Adult↗
PubMed2003

Heart failure mortality among older Medicare beneficiaries: association with left ventricular function evaluation and angiotensin-converting enzyme inhibitor use.

BACKGROUND: Left ventricular function evaluation and angiotensin-converting enzyme (ACE) inhibitor use are the two basic indicators of heart failure quality of care. In this retrospective follow-up study, we analyzed the association between these two quality indicators and mortality in elderly hospitalized heart failure patients. METHODS: The patients in our study were older Alabama Medicare beneficiaries discharged with a diagnosis of heart failure in 1994. Cox regression analyses, adjusted for various patient and care characteristics, were performed to estimate the overall mortality rate. RESULTS: The mean age of the 1,090 patients in our study was 79+/-7.5 years. Both left ventricular function evaluation (hazard ratio, 0.83; 95% confidence interval, 0.705-0.976) and ACE inhibitor use (hazard ratio, 0.77; 95% confidence interval, 0.655-0.905) were associated with a lower 3-year mortality rate. Adjustment for various patient and care characteristics did not alter these associations. CONCLUSION: Left ventricular function evaluation and ACE inhibitor use were each associated with increased survival time in older Medicare beneficiaries with heart failure.

Age Factors↗
PubMed1992

Effects of metabolic control on ventricular function in type 2 diabetic patients.

The effects of the metabolic changes of type 2 diabetic patients on ventricular function, especially diastolic ventricular function were investigated. An examination was performed before and after treatment of 18 diabetic patients divided into 3 groups: insulin therapy, oral hypoglycemic drugs and diet therapy (6 patients each). The results indicated that both systolic and diastolic ventricular dysfunctions observed were improved by the correction of hyperglycemia. Therefore it is necessary to treat diabetes mellitus as early as possible for the prevention of both cardiac dysfunction and microangiopathy.

Adult↗
PubMed1995

Improved left ventricular function after thiamine supplementation in patients with congestive heart failure receiving long-term furosemide therapy.

PURPOSE: We have previously found thiamine (vitamin B1) deficiency in patients with congestive heart failure (CHF) who had received long-term furosemide therapy. In the present study, we assessed the effect of thiamine repletion on thiamine status, functional capacity, and left ventricular ejection fraction (LVEF) in patients with moderate to severe CHF who had received furosemide in doses of 80 mg/d or more for at least 3 months. PATIENTS AND METHODS: Thirty patients were randomized to 1 week of double-blind inpatient therapy with either i.v. thiamine 200 mg/d or placebo (n = 15 each). All previous drugs were continued. Following discharge, all 30 patients received oral thiamine 200 mg/d as outpatients for 6 weeks. Thiamine status was determined by the erythrocyte thiamine-pyrophosphate effect (TPPE). LVEF was determined by echocardiography. RESULTS: TPPE, diuresis, and LVEF were unchanged with i.v. placebo. After i.v. thiamine, TPPE decreased (11.7% +/- 6.5% to 5.4% +/- 3.2%; P < 0.01). LVEF increased (0.28 +/- 0.11 to 0.32 +/- 0.09; P < 0.05), as did diuresis (1,731 +/- 800 mL/d to 2,389 +/- 752 mL/d; P < 0.02), and sodium excretion (84 +/- 52 mEq/d to 116 +/- 83 mEq/d, P < 0.05). In the 27 patients completing the full 7-week intervention, LVEF rose by 22% (0.27 +/- 0.10 to 0.33 +/- 0.11, P < 0.01). CONCLUSIONS: Thiamine repletion can improve left ventricular function and biochemical evidence of thiamine deficiency in some patients with moderate-to-severe CHF who are receiving longterm furosemide therapy.

Aged↗
PubMed1996

Randomized study of right ventricular function with intermittent warm or cold cardioplegia.

BACKGROUND: Transient right ventricular dysfunction has been previously documented after bypass operations despite adequate myocardial protection with intermittent antegrade cold blood cardioplegia. Recently warm blood cardioplegia has been interrupted during construction of distal anastomoses to improve visualization. The effects of intermittent antegrade warm blood cardioplegia, and the resultant periods of right ventricular normothermic ischemia, on postoperative right ventricular function are unknown. METHODS: To assess the effects of cardioplegia on right ventricular protection, 52 patients undergoing isolated bypass grafting were randomized to intermittent warm or cold blood cardioplegia. The two groups were similar with respect to age, sex, ventricular function, and right coronary stenoses. Cross-clamp times were similar (warm, 64 +/- 22 minutes; cold, 63 +/- 15 minutes; not significant). The cumulative time of cardioplegia interruption was longer in the cold group (42 +/- 8 minutes) than in the warm group (31 +/- 14 minutes; p < 0.002). A rapid-response thermodilution catheter was employed to assess postoperative right ventricular ejection fraction and end-diastolic and end-systolic volume indices. RESULTS: The right ventricular ejection fraction was greater in the warm group at 6 hours (warm, 0.46 +/- 0.06; cold, 0.37 +/- 0.08; p < 0.05) and 8 hours (warm, 0.43 +/- 0.08; cold, 0.37 +/- 0.08; p < 0.05) postoperatively. The right ventricular end-diastolic volume index was less in the warm group 8 hours postoperatively (warm, 83 +/- 11 mL/m2; cold, 94 +/- 16 mL/m2; p < 0.05). There were no differences in pulmonary arterial pressures or right ventricular stroke work index. CONCLUSIONS: Despite intermittent normothermic ischemia of half the cross-clamp time, patients receiving warm cardioplegia maintained right ventricular hemodynamics after bypass grafting.

Aged↗
PubMed1991

[The effect of nifedipine and diltiazem on left ventricular function in patients with stable angina pectoris and severe left ventricular dysfunction].

In a double blind crossover five-week trial with a randomized onset in 12 patients with normal blood pressure, stable angina pectoris and more severe left ventricular dysfunction (ejection fraction less than or equal to 40%) the effect of placebo nifedipine and diltiazem on left ventricular function and tolerance of exercise was compared. The investigation was done by means of echocardiography after a load with stimulation of the heart by an oesophageal electrode. As compared with placebo, only diltiazem retarded significantly the period before development of stenocardia on stimulation of the heart. There was no significant difference between nifedipine and diltiazem as regards the effect exerted on the ejection fraction and time which elapsed after stimulation before stenocardia developed. The authors observed an unequal response of patients to the administration of nifedipine and diltiazem (some patients had less favourable findings, although they were not subjectively aware of this deterioration). Therefore these drugs must be administered to patients with angina pectoris and more severe left ventricular dysfunction with care and only if other drugs (nitrates or angiotensin convertase inhibitors) do not eliminate ischaemia and pain.

Adult↗
PubMed2006

Echocardiographic measurement of ventricular function.

PURPOSE OF REVIEW: We review new findings concerning ventricular function in patients in intensive care units with shock or unexplained respiratory distress syndrome analyzed using echocardiography. RECENT FINDINGS: Bedside echocardiography is not only an imaging technique but should be considered as a hemodynamic method. Left-ventricular systolic function can be assessed in daily clinical practice by measuring shortening fraction, fraction area change and ejection fraction. But these indices are dependent on load conditions. Index of myocardial performance can be also used. Rate of left-ventricular pressure increase may be measured from mitral regurgitation. Other indices such a maximal elastance and preload-adjusted maximal power were developed to evaluate myocardial systolic function but are not still used in clinical practice in patients in intensive care. Cardiac output measurement can be calculated easily from aortic annulus diameter and the velocity time integral of aortic blood flow. To complete the assessment of ventricular function, left-ventricular diastolic function and pressure as well as right ventricular size, septal movement and right pressures should be analyzed. SUMMARY: Using echocardiography the intensivist can examine both the mechanism and the cause of shock or pulmonary edema. It is time to increase the use of this technique in intensive care units.

Atrial Function, Right↗
PubMed1981

Left ventricular function in diabetes mellitus. I: Methodology, and prevalence and spectrum of abnormalities.

Frequent abnormalities of left ventricular function were detected in 212 established diabetic patients using non-invasive techniques. Diabetics without angina or heart failure (n = 185) were significantly different from normal subjects (n = 50) in beat-to-beat variation, ratio of pre-ejection period to left ventricular ejection time, pre-ejection period index, isovolumic relaxation time, and interval from minimal dimension to mitral valve opening. Diabetics with angina (n = 18) were similar to control subjects with angina (n = 25); they showed a significant dimension change during the isovolumic period as compared with other diabetics and normals. Sixteen diabetics without angina also showed outward motion during the isovolumic period (incoordinate relaxation) and 13 had abnormal systolic time intervals. Four diabetics suffered a myocardial infarction during the study period; all had previously shown incoordination. Comparison of diabetics with a diastolic blood pressure below 100 mmHg and between 100 and 125 mmHg showed that the latter had a thicker posterior wall; the enlarged systolic dimension and reduced fractional shortening were the result of the inclusion of five of the 11 diabetic subjects with heart failure in the hypertensive group. Insulin-dependent diabetics tend to have more pronounced abnormalities of left ventricular function than those not requiring insulin. Patients selected from a diabetic clinic frequently have impaired left ventricular function, and ventricular hypertrophy, when present, in primarily caused by hypertension.

Adult↗
PubMed1998

Improvement of left ventricular function and cardiovascular neural control after endoventriculoplasty and myocardial revascularization.

OBJECTIVE: To investigate the effects of endoventriculoplasty (EVP) and myocardial revascularization on left ventricular function and on sympathovagal balance modulating sinus node and vasomotor activity, we studied patients with left anterior, septal or anteroseptal ventricular aneurysm, before and after surgery. It has been demonstrated that, compared to the standard aneurismectomy, EVP associated with coronary grafting has a lower operative mortality and improves ventricular function, clinical status and prognosis. METHODS: We collected pre- and post-operative echocardiographic and angiographic data to determine morphological and hemodynamic changes. The pre- and post-operative neural cardiovascular control was assessed by power spectrum analysis of heart rate and systolic arterial pressure (SAP) variabilities during rest and tilt. RESULTS: As expected, post-operative ventricular function improved significantly: ejection fraction increased from 33 +/- 2 to 46 +/- 3% (p < 0.01) when assessed by echocardiography and from 40 +/- 4 to 55 +/- 5% (p < 0.01) when assessed by angiography; left ventricular end-diastolic pressure fell from 22 +/- 3 to 13 +/- 2 mmHg (p < 0.05). Pre-operatively sympathovagal balance responsiveness was blunted: tilt test did not induce, in respect to resting values, any significant change in low frequency (LFRR) and high frequency (HFRR) components of RR variability (in normalized units, n.u.) and in LFSAP. Post-operatively, tilt induced significant changes in LFRR and HFRR (in n.u.), in LF/HF ratio and LFSAP in respect to resting values. The pre- and post-operative percent differences--delta%--, from rest to tilt, of LFRR, HFRR, LF/HF and LFSAP were also significantly different (p < 0.01, p < 0.05, p < 0.05, p < 0.05). In addition, we compared data obtained from survivors and non-survivors (6 out of 19 patients died within 4 months because of heart failure). Non-survivors were characterized by significantly lower RR variance (184 +/- 80 vs. 1193 +/- 309 ms2 at rest, 196 +/- 87 vs. 546 +/- 104 ms2 during tilt, p < 0.05) and lower LFRR (15 +/- 7 vs. 61 +/- 6 at rest, 23 +/- 10 vs. 58 +/- 6 during tilt, in n.u., p < 0.01). CONCLUSIONS: (1) The improvement of ventricular function induced by EVP and myocardial revascularization is accompanied by a restored capability to oscillate of cardiovascular neural regulatory mechanisms; (2) the drastic reduction of variance and LF component from RR variability seems to be associated with an ominous outcome.

Aged↗
PubMed1992

Decreased concentration of myofibrils and myofiber hypertrophy are structural determinants of impaired left ventricular function in patients with chronic heart diseases: a multiple logistic regression analysis.

OBJECTIVES: The aim of this study was to perform a multiple logistic regression analysis to identify independent structural determinants of impaired left ventricular function. BACKGROUND: The association between contractile failure and structural alterations of the myocardium has been demonstrated in several studies, and multiple interactions between myocardial structure and cardiac performance are likely. METHODS: Morphometric data assessed from 130 left ventricular biopsy specimens were analyzed. The endomyocardial specimens were obtained from 57 patients with normal coronary arteries (17 with normal left ventricular ejection fraction and 40 with impaired left ventricular function [dilated cardiomyopathy]), 15 patients with hypertrophic cardiomyopathy and 32 patients with aortic valve disease. Transmural biopsy specimens were assessed in 6 donor hearts before heart transplantation and in 20 patients with left anterior descending coronary artery disease whose specimens were obtained from the left ventricular anterior wall during aortocoronary bypass surgery. Global or regional left ventricular function was evaluated from left cineventriculograms. The volume fraction of cardiac fibrous tissue, intracellular volume fraction of myofibrils, volume fraction of myofibrils related to myocardial tissue (including fibrosis) and myofiber diameters were determined from semithin sections of the biopsy specimens with the use of light microscopic morphometry. RESULTS: Multiple logistic regression analysis revealed decreased volume fraction of myofibrils (p < 0.005) and increased fiber diameter (p < 0.002) as independent determinants of impaired left ventricular function. CONCLUSIONS: These data indicate that, independent of the underlying heart disease, both decreased concentration of contractile proteins and myocyte hypertrophy are independently associated with impaired left ventricular function.

Age Factors↗