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PubMed1985

Comparison of ventricular function after Senning and Jatene procedures for complete transposition of the great arteries.

Postoperative right (RV) and left ventricular (LV) volume characteristics in patients with complete transposition of the great arteries were studied to compare ventricular function after Senning and Jatene procedures and to analyze RV dimensional change during systole in patients after the Senning procedures. RV end-diastolic volume (EDV) was 181 +/- 74% of normal (mean +/- standard deviation) and RV ejection fraction (EF) was 0.48 +/- 0.09 in 15 patients who underwent the Senning procedure. In 9 patients who underwent the Jatene procedure, LVEDV was 152 +/- 27% of normal and LVEF was 0.61 +/- 0.09. One patient with aortic regurgitation, 1 with aortic regurgitation and residual ventricular septal defect, and 1 with aortic regurgitation and generalized LV wall hypokinesia of unknown cause had large LVEDVs. Pulmonary ventricular EDV and EF were within normal ranges except in the patients with persistent pulmonary hypertension, who had large EDVs and low EFs regardless of the anatomic type of ventricle, either the left or right. The study of RV dimensional change in the Senning group showed a reduced systolic shortening of the anteroposterior diameter compared with the preoperative transposition of the great arteries and normal. This reduced shortening may be related to postoperative adhesion of the RV free wall to the anterior chest wall and fixation of the atrium secondary to the intraatrial repair. In conclusion, systemic ventricular function after intraatrial repair for complete transposition of the great arteries is depressed by unavoidable residua and sequelae: persistent RV hypertension, anatomy of the right ventricle and, possibly, postoperative adhesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Surgical Procedures↗
PubMed1975

[Effect of coronary bypass surgery on myocardial pressure and ventricular function in the dog].

In 7 dogs a severe stenosis of the left circumflex coronary artery (CCA) is produced in the course of 18 days. The influence of myocardial revascularization on left ventricular function and on intramyocardial pressures in the areas supplied by the CCA and by the left anterior descending coronary artery is studied. Neither under control conditions nor during acute left ventricular pressure load does opening a bypass graft between the carotid artery and CCA induce a significant change in total ventricular function (dp/dtmax, Vmax, left ventricular enddiastolic pressure). However, immediately after opening the graft intramyocardial pressure rises in the CCA area indicating a regional improvement of myocardial function.

Animals↗
PubMed2006

[Quantification of right and left ventricular function with magnetic resonance imaging after Senning operation for complete transposition of the great arteries].

INTRODUCTION: The different non-invasive examinations do not result in unambigous results about the long-term determination of right ventricular function providing systemic circulation in children with transposition of the great arteries operated with Senning procedure. AIM: The goal of study was to determine the application of MRI for the observation of right and left ventricular morphology and function, for the recognition of the progression of the disease, and for the necessity of reoperation. METHODS: The authors have observed the morphology and function of the right and left ventricule by ECG triggered short axis MR pictures. For the analysis of MR pictures MASS 5.0 software was used. Authors have determined the end systolic and end diastolic volume, the ejection fraction, the mass, and the stroke volume of the right ventricule, the end systolic and end diastolic volume, ejection fraction, the mass, and the stroke volume of the left ventricle, and the shunt volume. The values of these data corrected to body mass have been calculated. PATIENTS: 176 Senning operations took place between 1980 and 1996. MRI exploration at 21 of the 118 analyzed patients were carried out. RESULTS: The right ventricular ejection fraction value at Senning operated patients is significantly different (49 +/- 9% vs. 70 +/- 4%) from those of healthy children (P < 0.01). Right ventricular stroke volume/m2 and right ventricular end systolic volume/m2 were significantly different compared to normal (43 +/- 10 ml/m2 vs. 48 +/- 7 ml/mn and 46 +/- 16 ml/m2 vs. 21 +/- 5 ml/m2, p < 0.05). Authors found also significant differences in left ventricular ejection fraction in Senning patients as compared to normal (60 +/- 9% vs. 70 +/- 6%, p < 0.01). CONCLUSION: MRI, which is a reliable method of objective determination of right ventricular function, became an available method in Hungary. According to the results, authors might presume that the development of right ventricular dysfunction is expected even among Senning operated children without clinical symptoms, so more frequent control is required. The pathological left ventricular parameters may be explained by ventricular interactions. Authors find MRI an important part of the complex follow-up protocol of Senning operations. MRI data extended by results of other non-invasive explorations are appropriate for the follow-up of right ventricular dysfunction.

Cardiac Surgical Procedures↗
PubMed1996

Impact on ventricular function and quality of life of transcatheter ablation of the atrioventricular junction in chronic atrial fibrillation with a normal ventricular response.

We assessed left ventricular function and quality of life after atrioventricular junction ablation and pacemaker implant in 14 patients with chronic atrial fibrillation and normal ventricular response. A significant improvement in left ventricular ejection fraction, fractional shortening, and functional capacity were observed at follow-up, suggesting that in patients with chronic atrial fibrillation a regular heart beat may be preferable over rate control.

Aged↗
PubMed2001

Comparison of the effects of angiotensin converting-enzyme inhibitors and beta blockers on survival in elderly patients with reduced left ventricular function after myocardial infarction.

PURPOSE: Angiotensin converting-enzyme (ACE) inhibitors decrease mortality after myocardial infarction among patients with depressed left ventricular function. Beta blockers may also improve survival in these patients. We compared the relative effects of these agents on the survival of elderly patients with a left ventricular ejection fraction less than 40% after myocardial infarction. SUBJECTS AND METHODS: The Cooperative Cardiovascular Project collected data on patients aged 65 years and older who were admitted with myocardial infarction from April 1994 to July 1995, including 20,902 with a measured left ventricular ejection fraction less than 40% before discharge. Using proportional hazard regression models that adjusted for patient characteristics and in-hospital treatments, we compared survival among patients discharged on ACE inhibitors, beta blockers, both medications, or neither medication. RESULTS: Among patients surviving hospitalization with reduced left ventricular function, 9,108 (44%) were discharged on ACE inhibitors, 2,613 (13%) on beta blockers, 3,309 (16%) on both medications, and 5,872 (28%) on neither medication. Patients treated with ACE inhibitors were more likely to have a prior diagnosis of heart failure and less likely to have undergone revascularization, whereas those treated with beta blockers were more often treated with thrombolytic therapy and aspirin. Patients treated with ACE inhibitors [hazard ratio (HR = 0.80), 0.80; 95% confidence interval (CI), 0.73 to 0.87] or beta blockers (HR = 0.76, 0.76; 95% CI, 0.64 to 0.90) had lower adjusted 1-year mortality than those who were not treated with either medication. The combination of both medications was associated with additional benefit (HR = 0.68, 0.68; 95% CI, 0.59 to 0.80). The relative benefit of each medication was greatest among patients with an ejection fraction less than 30%, a serum creatinine level 2.0 mg/dL or greater, or both. To prevent a death within a year, the number of patients who needed to be treated with both medications varied from 5 to 15, depending on ejection fraction and renal function. CONCLUSION: ACE inhibitors and beta blockers were associated with similar improvements in survival among elderly patients with reduced left ventricular ejection fraction after myocardial infarction. Our results suggest that patients who can tolerate both medications gain additional benefit from the combination.

Adrenergic beta-Antagonists↗
PubMed1987

Right ventricular function in dilated cardiomyopathy.

The right ventricular (RV) function was comprehensively examined in 18 patients with dilated cardiomyopathy (DCMP) and compared with RV function in 10 controls. In most cases of DCMP, the RV function is affected simultaneously with a disturbance of the left ventricular (LV) function. However, the degree of its affection is usually less pronounced and, with less severe LV dysfunction, the right ventricle can work even normally. There can be substantial individual differences in the degree of affection of the right ventricle in DCMP. However, severe LV dysfunction is invariably associated with a marked involvement of the right ventricle. A disturbance of the RV function results (besides the influence of the decreased LV function) from both a decrease in its own contractility and a decrease in RV compliance. There exist significant relations between the RV systolic and diastolic function. The degree of RV disturbance in DCMP both of the systolic and diastolic function) can be approximately estimated from the level of diastolic pressure.

Cardiomyopathy, Dilated↗
PubMed1987

[Left ventricular function at rest and during exercise and the effects of propranolol in patients with hypertrophic cardiomyopathy].

To determine left ventricular function during the stress of exercise and to evaluate the effects of propranolol on it in patients with hypertrophic cardiomyopathy (HCM), the ECG-multigated blood pool cardiac scintigraphy was performed in 12 without (HNCM) and 10 with (HOCM) left ventricular outflow obstruction at rest and during bicycle ergometer loading. The results were compared to those in 13 normal subjects. 1. Control measurements: Resting and exercise heart rates and blood pressures did not significantly differ between patients with hypertrophic cardiomyopathy and normal subjects. Ejection fraction (EF) was normal or higher in HCM than in normal subjects at rest, but during exercise it failed to increase normally. The increment in cardiac output was half of the normal value. Responses of count-derived end-diastolic volume (EDV) and stroke volume (SV) were different between HOCM and HNCM. They were unchanged during exercise in HNCM and declined in HOCM. End-systolic volume (ESV) was unchanged in HNCM and slightly decreased in HOCM. Responses of the peak ejection rate (PER) and time to the peak ejection rate (TPE) were not significantly different from normal subjects. Left ventricular (LV) ejection time (ET) and TPE/ET were not different from normal subjects. The peak filling rate (PFR) was significantly higher than normal in HOCM at rest and during exercise. The time to peak filling rate was prolonged at rest in HOCM, but not during exercise. 2. Effects of propranolol: Heart rates significantly decreased especially after intravenous propranolol administration. Cardiac output (CO) and SV were unchanged. EDV and ESV increased significantly. The PER was unchanged. The PFR decreased, but not significantly. TPE, time to the PFR (TPF) and ET were prolonged. The ratio of TPE/ET decreased initially, but abruptly increased later. In conclusion, in the control state of HCM patients, the responses of LVEF, EDV and ESV to exercise were abnormal and CO remained half of the normal. There was no difference between patients with and without obstruction. The effect of propranolol on left ventricular function was more obvious in patients with obstruction than without obstruction, especially in ESV, EDV, PFR and TPF. Propranolol did not improve LV systolic and diastolic functions, but the double product decreased depending on the decrease of heart rate maintaining CO by Frank-Starling mechanism due to increased EDV, which may play a part in improving subjective complaints.

Administration, Oral↗
PubMed1995

Right ventricular function and plasma atrial natriuretic peptide levels during fiberbronchoscopic alveolar lavage in critically ill, mechanically ventilated patients.

STUDY OBJECTIVE: To assess the influence of fiberbronchoscopic alveolar lavage on hemodynamics, right ventricular function, and plasma atrial natriuretic peptide (ANP) concentrations in critically ill, mechanically ventilated patients. DESIGN: Prospective investigation. SETTING: Eight-bed ICU of a university hospital. PATIENTS: Fourteen patients with cardiovascular instability due to a systemic inflammatory response syndrome who were mechanically ventilated. INTERVENTIONS: Fiberbronchoscopic alveolar lavage after fluid replacement, deep sedation, and paralyzation. Intervention time: 10 min. After inspection of the endobronchial system, one lavage of 40 mL sterile saline solution was instilled in each lung and recovered. MEASUREMENTS AND RESULTS: The fiberbronchoscopic procedure induced a prompt increase in mean pulmonary arterial pressure after 3 min (median[range]: 25 [13 to 39] to 30 [19 to 45] mm Hg, p < 0.05), which increased further after 6 min (34 [17 to 46] mm Hg, p < 0.01). Cardiac index increased simultaneously (4.25 [3.1 to 5.7] to 4.85 [4.3 to 6.9] L/min.m2 after 6 min, p < 0.01), whereas mean arterial pressure and heart rate remained unchanged. Central venous pressure rose from 12 (3 to 18) mm Hg before procedure to 14 (4 to 20) mm Hg after 6 min (p < 0.01). The right ventricular function was measured using a "fast response" ejection fraction thermodilution catheter: end-diastolic volume increased (238 [137 to 358] to 280 [150 to 4ll] mL after 9 min, p < 0.05), as well as stroke volume (88 [54 to 113] to 103 [67 to 153] mL after 9 min, p < 0.01). Right ventricular ejection fraction (37 [25 to 50] %) did not change significantly during the procedure, but the stroke work index was reinforced (8.2 [4.7 to 15.7] to 13.3 [2.4 to 41.3] gm.M/M2 after 6 min, p < 0.01). Plasma c-ANP concentration rose from 135 (24 to 350) to 196.5 (44 to 830 pg/ml after 20 min (p < 0.05). Systemic vascular resistance decreased from 533 (390 to 1,042) to 429 (281 to 684) dynes.s/cm5 after removal of the bronchoscope (p < 0.01). CONCLUSIONS: Although acute pulmonary hypertension was observed during the fiberbronchoscopic procedure, the right ventricular performance did not deteriorate in hemodynamically unstable patients. To maintain a "hyperdynamic cardiovascular state," the right ventricular stroke work was reinforced, presumably by the "Frank-Starling mechanism." We assume that the acute distention of the right side of the heart resulted in elevated ANP concentrations. The marked decrease in systemic vascular resistance might be due to high ANP levels.

Adult↗
PubMed1998

Acute effects of transmyocardial laser revascularization on left-ventricular function: an haemodynamic and echocardiographic study.

While the lesions produced by transmyocardial laser revascularisation (TMLR) induce scar formation, it is important to determine whether this procedure can be deleterious for the left-ventricular function, which is already impaired by the underlying ischaemic process in some patients. Ten channels were drilled in the left lateral wall of the hearts of ten pigs (mean weight, 61 +/- 8.2kg) with a Holmium:YAG laser. Haemodynamic measurements and echocardiographic assessment of left-ventricular function were performed before the TMLR procedure, 5 and 30 min after, and lastly after 5 min of pacing at a rate increased by 30% of the baseline value. Echocardiographic assessment was in the short axis at the level of the laser channels, and included left-ventricular ejection fraction and segmental wall motility of the lasered area (scale 0-3:0 = normal 1 = hypokinesia, 2 = akinesia, 3 = dyskinesia). Values at 5 and 30 min were compared with baseline values; the difference was considered significant if p < 0.05. Haemodynamical values were stable throughout all the procedures. The ejection fraction showed a slight but significant decrease 5 min after the creation of the channels (60.4 +/- 6.8% vs 54 +/- 7.6%, p=0.02) and recovered at 30min. The segmental motility score of the involved areas increased to 1 after 5 min in five animals, and came back to 0 at 30 min except in one animal. Even with pacing no segmental dysfunction occurred. The reversibility of the segmental hypokinesia induced by TMLR, as well as the absence of pace-induced dysfunction 30 min after the procedure strongly suggest the inocuity of TMLR in this experimental set-up.

Animals↗
PubMed1983

The importance of the mitral apparatus in left ventricular function after correction of mitral regurgitation.

This study evaluates the possible role of the mitral apparatus in left ventricular function after correction of chronic mitral regurgitation. Seventeen patients underwent complete preoperative and early postoperative heart catheterization. Six patients underwent conventional mitral valve replacement (group 1), six mitral valve replacement with preservation of chordae tendineae and papillary muscles (group 2), and five mitral valvuloplasty (group 3). There was no statistically significant difference among the three groups for any hemodynamic parameter as compared before surgery by analysis of variance. After correction of mitral regurgitation the increase in cardiac index was similar for all three groups. Left ventricular end-diastolic volume did not decrease significantly in group 1 (p = NS), but it did in groups 2 and 3 (p less than .005 for both). Left ventricular end-systolic volume increased in group 1 (p less than .025) and decreased in groups 2 and 3 (p less than .01 and .005, respectively). Ejection fraction decreased in group 1 (p less than .005) and did not change in groups 2 or 3 (p = NS). Left ventricular end-diastolic pressure increased in group 1 (p less than .005) and decreased in groups 2 and 3 (p less than .01 for both). These findings suggest that continuity between mitral anulus and left ventricular wall through leaflets, chordae tendineae, and papillary muscles plays a role in left ventricular function after correction of the chronic mitral regurgitation.

Adult↗
PubMed1976

The influence of ventricular function on the results of aortic valve replacement for aortic stenosis.

Thirty-three patients who had aortic valve replacement (AVR) for isolated aortic stenosis (AS) were retrospectively evaluated to determine the influence of preoperative ventricular function on the results of operation. Patients were arbitrarily divided by ejection fraction (EF) into Group I having EF 0.46 or above and Group II having EF 0.45 or below. Group II had significantly lower mean EF and cardiac index and higher left ventricular end-diastolic volume index and end-diastolic pressure. There were two early and no late deaths in 21 Group I patients. There were no early and five late deaths in 12 Group II patients. All Group I survivors and six of 12 Group II patients were New York Heart Association (NYHA) functional Class I or II at follow-up evaluation. No preoperative hemodynamic index was predictive of which Group II patients would do well. Mortality was substantially higher in patients with severe preoperative disability. Early or late death occurred in five of 12 patients who were NYHA functional Class IV before operation but in only two of 21 patients who were functional Class II or III preoperatively. We conclude that patients with isolated AS and poor left ventricular function have a low hospital mortality but an increased risk of late death or poor functional result following AVR. Excellent functional results can be obtained after AVR in most patients with AS and good left ventricular function and approximately half of the patients with AS and poor left ventricular function.

Adult↗
PubMed1999

[The effects cervicothoracic sympathetic blockade on left ventricular function].

OBJECTIVE: Cervicothoracic sympathetic blocks (stellate ganglion blocks) not only influence pain, but also lead to regional sympathetic denervation of part of the left ventricular wall, while other ventricular regions stay under the control of the unblocked side. What is the influence of these imbalances of sympathetic innervation on ventricular function? METHODS: Thirteen anaesthetised dogs were instrumented for measurement of left ventricular pressure (tip-manometer), cardiac output (ultrasonic flow probe) and regional myocardial function (sonomicrometry) in two left ventricular regions, innervated by the left or right sympathetic system, respectively. Electrical stimulations of the left and right stellate ganglia, and left and right sided stellate ganglion blocks were performed. In eight patients with no cardiac disease, the effects of left stellate ganglion blocks on echocardiographic variables of ventricular function were investigated. RESULTS: In dogs, the unilateral ganglion stimulations led to an increase in regional and global contractility. However, left ventricular wall motion became asynchronous and, despite an increase in contractility, relaxation was impaired. After the ganglion blocks, there was a decrease in regional contractility within the denervated area, also leading to an asynchronous wall motion. As a consequence, relaxation was impaired, but cardiac output was maintained. In the patients, there was an increase in isovolumic relaxation time. This change was also within the compensatory range and cardiac output increased slightly as a consequence of a simultaneous afterload reduction by the ganglion block. CONCLUSION: The studies show a disturbance of diastolic function after stellate ganglion blocks, resulting from an asynchronous wall motion pattern after the regional denervation. However, the changes were within the compensatory range of a healthy ventricle and cardiac output was not reduced.

Anesthesia, Spinal↗
PubMed2002

Myocardial enhancement on magnetic resonance imaging with gadolinium-diethylenetriamine pentaacetic acid and improvement of left ventricular function in patients with dilated cardiomyopathy.

OBJECTIVES: This study evaluated the significance of myocardial gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) enhancement on magnetic resonance imaging for the improvement of left ventricular function in patients with dilated cardiomyopathy. METHODS: Twenty-seven patients with dilated cardiomyopathy (mean age 59 +/- 11 years) were studied. The magnitude of myocardial Gd-DTPA enhancement was quantitatively assessed using signal intensity ratio and compared to changes in left ventricular function and adverse cardiac events during a relatively long follow-up period. RESULTS: Regional high signal intensity ratio, defined as > or = mean + 2SD in seven normal subjects, was found in 14 patients: in three or more regions out of five myocardial regions analyzed in six patients (extensive enhancement) and in only one or two regions in eight patients (limited enhancement). The remaining 13 patients had no high signal ratio in any of the five regions analyzed (no enhancement). During the follow-up period of 3.9 +/- 1.9 years, four patients died of cardiac causes. The incidence of cardiac death was 33.3% in patients with extensive enhancement, 12.5% in those with limited enhancement and 7.7% in those without enhancement, but there was no statistical difference. Mild improvement in fractional shortening was observed in patients without enhancement during the follow-up (19 +/- 4%-->27 +/- 10%, p = 0.03). CONCLUSIONS: Evaluation of myocardial Gd-DTPA enhancement on magnetic resonance imaging may provide useful prognostic information for patients with dilated cardiomyopathy.

Adult↗
PubMed1997

The effect of preoperative intra-aortic balloon pump support in patients with coronary artery disease, poor left-ventricular function (LVEF < 40%), and hypertensive LV hypertrophy.

Poor left-ventricular function, hypertension, and left-ventricular hypertrophy in patients with coronary artery disease (CAD) undergoing coronary artery bypass grafting (CABG) are associated with increased operative risks. Between June 1994 and March 1996, 33 patients undergoing CABG, were randomized into 2 groups. One group (IABP group, n = 19) received IABP treatment on average for 2 hours prior to CPB, the other group (control group, n = 14) had no preoperative IABP, Cardiac performance was measured pre- and postoperatively by Swan-Ganz catheter. Mean age was 65 years and 90% were men. All patients had a preoperative LVEF < or = 40% (mean 32.6 +/- 11.1%), 3-vessel disease, established hypertension (WHO criteria), and LV hypertrophy (ventricular mass > or = 136 g/m2 [men] or > or = 110 g/m2 [women]). Ischemia time was similar in both groups while CPB-time was shorter in the IABP group, p < 0.05. There were no hospital deaths in the IABP group, but 3 in the control group suffered postoperative low cardiac output. Nine patients (64%) in the control group required IABP support postoperatively, but only 20% of the patients in the IABP group had a shorter ICU stay, 2.4 +/- 0.9 vs. 3.4 +/- 1.1 days, p < 0.01. Cardiac index increased significantly in the IABP group prior to CPB and was higher compared to control, p < 0.001. Five min after CBP cardiac index was higher in the IABP group than in the control group, p = 0.013, and continued to increase thereafter, while no further improvement was observed in controls. Preoperative IABP treatment in hypertensive patients with CAD, low LVEF and LV hypertrophy who are undergoing CABG is beneficial. An improved cardiac performance pre- and postoperatively was associated with a lower rate of hospital mortality and less postoperative morbidity, as well as shorter ICU stay. The treatment is cost-beneficial.

Adult↗
PubMed1997

The effect of milrinone on hemodynamics and left ventricular function after emergence from cardiopulmonary bypass.

Although milrinone effectively increases cardiac function, few studies have specifically evaluated its efficacy during cardiac surgery. We investigated the effects of milrinone on hemodynamics and left ventricular function in cardiac surgical patients who were already treated with catecholamines. Thirty-seven patients undergoing cardiac surgery were studied. Immediately after emergence from cardiopulmonary bypass (CPB), patients were randomly assigned to a control group (n = 10) or to one of these milrinone groups: milrinone 50 microg/kg intravenously (n = 8), 50 microg/kg + 0.5 microg x kg(-1) x min(-1) (n = 10), or 75 microg/kg + 0.75 microg x kg(-1) x min(-1) (n = 9). Hemodynamics and transesophageal echocardiogram were recorded while constant filling pressures were maintained by volume reinfusion from the CPB reservoir. Arterial blood samples were obtained for the measurement of milrinone plasma concentrations and to determine the dose response curve. In all three milrinone groups, cardiac index and velocity of circumferential fiber shortening (Vcfc) significantly increased from the baseline, and both were significantly higher at 5 and 10 min than those in the control group. The plasma concentration of milrinone with half of maximum increase in Vcfc was 139.3 ng/mL based on the dose-response curve. Thus, milrinone improves hemodynamics and left ventricular function when constant loading conditions are maintained.

Cardiac Surgical Procedures↗
PubMed1997

Relationship of blood flow effects of adenosine during reperfusion to recovery of ventricular function after hypothermic ischemia in neonatal lambs.

BACKGROUND: Previous experiments have shown that infusion of either adenosine (ADO) or an adenosine receptor agonist during reperfusion after hypothermic ischemia improved the recovery of ventricular function in neonatal lamb hearts. Adenosine has multiple actions that might be beneficial during postischemic reperfusion, and the A2 effects include both coronary vasodilator and leukocyte inhibitory effects. In the current experiment we investigated the relationship between the coronary blood flow (CBF) effects of A2 stimulation and the recovery of postischemic ventricular function. METHODS AND RESULTS: Two hours of 10 degrees C cardioplegic ischemia was induced in 40 isolated, blood-perfused, neonatal lamb hearts (n=8 in each group). Group I had ischemia followed by unmodified reperfusion for 90 minutes. During the first 20 minutes of reperfusion, Group II received 350 micromol/L ADO, Group III received ADO and 100 nmol/L DPCPX (A1 antagonist) to achieve an A2 effect, Group IV received 0.25 micromol/L CPCA (A2 agonist), and Group V received ADO and DPCPX but CBF was limited to that of Group I levels. At 30 and 90 minutes of reperfusion, LV maximum developed pressure (DP), dP/dt, CBF, and oxygen consumption (MVO2) were measured. At 30 minutes of reperfusion Groups II, III, and IV showed better functional recovery than Group I or Group V (DP: G-I=75.7+/-7.3%, G-II=97.6+/-9.5%, G-III=88.1+/-4.8%, G-IV=86.7+/-9.0%, G-V=75.5+/-6.9%, P<.05; dP/dt: G-I=69.1+/-9.6%, G-II=94.2+/-10.7%, G-III=95.7+/-13.1%, G-IV=80.1+/-11.1%, G-V=75.2+/-8.2%, P<.05). Coronary blood flow was higher in Groups II, III, and IV compared with Group I or V (G-1=129+/-32%, G-II=183+/-36%, G-III=266+/-72%, G-IV=259+/-70%, G-V=132+/-5%, P<.05). MVO2/beat was higher in Group II than in Groups I and IV (G-I=98.3+/-21.3%, G-II=135.5+/-28.0%, G-III=126.2+/-21.9%, G-IV=102.5+/-16.7%, G-V=107.5+/-29.3%, P<.05). At 90 minutes of reperfusion, Groups II, III, and IV, as well as V, showed better recovery of DP and dP/dt compared with Group I (DP: G-I=50.6+/-11.4%, G-II=63.0+/-8.7%, G-III=69.0+/-10.8%, G-IV=72.5+/-12.7%, G-V=66.2+/-10.0%, P<.05; dP/dt: G-I=38.9+/-7.1%, G-II=53.5 +/-3.8%, G-III=61.5+/-10.8%, G-IV=59.8+/-16.3%, G-V=58.2+/-9.8%, P<.05) although only in Groups III and IV was CBF higher than in Group I (G-1=116+/-54%, G-II=116+/-27%, G-III=210+/-67%, G-IV=239+/-85%, G-V=130+/-8%, P<.05). CONCLUSIONS: Reperfusion under conditions of A2 stimulation by ADO, by an A2 agonist, or by ADO plus A1 blockade was associated with improved recovery of LV function. The early A2 effect seems to be related to coronary vasodilation because reduced CBF (equal to Group I) in Group V reduced early recovery of LV function. However, there seems to be a second effect observed at 90 minutes that is not related to CBF inasmuch as Groups II and V had CBF equal to Group I but had significantly higher DP and dP/dt. These findings suggest that mechanisms in addition to vasodilation are involved in the beneficial effects of A2 stimulation during postischemic reperfusion.

Adenosine↗
PubMed1997

Variable effects of cardiomyoplasty on left ventricular function.

Cardiomyoplasty (CMP) has been considered as a possible treatment for patients with heart failure. Symptomatic improvements occur almost uniformly among survivors with CMP, but changes in left peak ventricular systolic pressure (PVSP) and stroke volume vary in patients. This study examined whether there is variability present shortly after cardiomyoplasty surgery. Cardiomyoplasty was performed in 11 mongrel dogs with normal ventricular function. Nine to twelve days after CMP, left ventricular (LV) function was evaluated by simultaneously measuring LV volume (conductance catheter) and pressure (Millar catheter). The latissimus dorsi muscle (LDM) was stimulated synchronously with ventricular systole in a ratio of 1:4 to 1:7 to avoid muscle fatigue. Data were analyzed on a beat by beat basis. The PVSP, and maximum dP/dt (+dP/dt) increased, but the absolute value of minimum dP/dt (-dP/dt) decreased in stimulated beats in 7 dogs while 4 dogs did not respond. The net changes in stimulated beats versus nonstimulated beats of PVSP were 6.1 +/- 1.8 mm Hg (4.3%), of stroke work was 4.5 +/- 1.9 gm x m (29.5%), of +dP/dt was 185 +/- 47 mm Hg/s (8%), and of -dP/dt was 168 +/- 43 mm Hg/s (7.8%) (p < 0.05) for all these net changes in the responding group while these variations were not significant in the nonresponding group. From the results of our study, active LDM assist improves left ventricular systolic function, occurring in only 7 of 11 experiments. This improvement is inconsistent and varied individually. The integrity of the LDM, tightness of wrapping, and adhesions might contribute to the variability which is present early after surgery and before the LDM is converted into a fatigue resistance muscle.

Animals↗
PubMed1985

Late results of surgical and medical therapy for patients with coronary artery disease and depressed left ventricular function.

Late survival and freedom from myocardial infarction were determined for 192 patients with coronary artery disease and depressed left ventricular ejection fraction at rest (less than or equal to 35%) determined by biplane angiography who were evaluated between 1970 and 1977. Seventy-seven patients had coronary artery bypass grafting and 115 patients were treated medically and were considered surgical candidates. The medical and surgical groups were comparable in all baseline characteristics examined except frequency of three vessel disease and angina pectoris, which occurred in a significantly greater percent of the surgically treated patients (p less than 0.01). Only three medically treated patients (2.6%) underwent coronary bypass grafting in the follow-up period. Seven year actuarial survival was 63% in the surgical and 34% in the medical group (p less than 0.001). Ninety-three percent of patients in the surgical group and 81% of those in the medical group were free of nonfatal myocardial infarction (p = 0.01), and 62 and 33%, respectively, were alive and free of myocardial infarction (p less than 0.001) at 7 years. Significant differences in survival favoring surgical treatment were observed for the subsets of patients with an ejection fraction of 25% or less (p = 0.0002) and 26 to 35% (p = 0.01), and for the subsets with three vessel coronary disease (p less than 0.001), normal left ventricular end-diastolic volume (less than or equal to 100 ml/m2) (p = 0.005) and elevated end-diastolic volume (greater than 100 ml/m2)(p = 0.001). After adjustment for other important prognostic variables, the type of treatment remained significant in predicting the relative risk (medical to surgical) of mortality at 5 and 7 years (2.58 and 2.12, respectively). These data corroborate the trends observed in several randomized trials of medical and surgical therapy in patients with abnormal left ventricular function. If hospital mortality for coronary artery bypass grafting is less than 5%, substantial benefit can be anticipated for the majority of patients with depressed ventricular function.

Cardiac Volume↗