Raul E. Falicov

Unstable angina pectoris: National cooperative study group to compare surgical and medical therapy: II. In-Hospital experience and initial follow-up results in patients with one, two and three vessel disease

Abstract A prospective randomized study comparing intensive medical therapy with urgent coronary bypass surgery for the acute management of patients with unstable angina pectoris was carried out by nine cooperating medical centers under the auspices of the National Heart, Lung, and Blood Institute. Between 1972 and 1976, a total of 288 patients were entered into the study. All patients had transient S-T or T wave changes, or both, in the electrocardiogram during pain; 90 percent had pain at rest in the hospital, and 76 percent had multivessel coronary disease. The medically and surgically treated patients were comparable with respect to clinical, electrocardiographic and angiographic characteristics and left ventricular function. During the total study period, the hospital mortality rate was 5 percent in the surgical group and 3 percent in the medical group (difference not significant). The rate of in-hospital myocardial infarction was 17 and 8 percent in the respective groups (P In the 1st year after hospital discharge class III or IV angina (New York Heart Association criteria) was more common in medically than in surgically treated patients with one vessel disease (22 percent versus 3 percent, P The results indicate that patients with unstable angina pectoris can be managed acutely with intensive medical therapy, including the administration of propranolol and long-acting nitrates in pharmacologic doses, with adequate control of pain in most patients and no increase in early mortality or myocardial infarction rates. Later, elective surgery can be performed with a low risk and good clinical results if the patients angina fails to respond to intensive medical therapy.

Unstable angina pectoris: National cooperative study group to compare medical and surgical therapy

A preliminary report is presented of a prospective randomized trial conducted by eight cooperative institutions under the auspices of the National Heart and Lung Institute to compare the effectiveness of medical and surgical therapy in the management of the acute stages of unstable angina pectoris. To date 150 patients have been included in the randomized trial, 80 assigned to medical and 70 to surgical therapy; the clinical presentation, coronary arterial anatomy and left ventricular function in the two groups are similar. Some physicians have been reluctant to prescribe medical or surgical therapy by a random process, and the eithical basis of the trial has been questioned. Since there are no hard data regarding the natural history and outcome of therapy for unstable angina pectoris, randomization appears to provide a rational way of selecting therapy. Furthermore, subsets of patients at high risk may emerge during the process of randomization. The design of this randomized trial is compared with that of another reported trial. Thus far, the study has shown that it is possible to conduct a randomized trial in patients with unstable angina pectoris, and that the medical and surgical groups have been similar in relation to the variables examined. The group as a whole presented with severe angina pectoris, either as a crescendo pattern or as new onset of angina at rest, and 84 percent had recurrence of pain while in the coronary care unit and receiving vigorous medical therapy. It is anticipated that sufficient patients will have been entered into the trial within the next 12 months to determine whether medical or surgical therapy is superior in the acute stages of unstable angina pectoris.Abstract A preliminary report is presented of a prospective randomized trial conducted by eight cooperative institutions under the auspices of the National Heart and Lung Institute to compare the effectiveness of medical and surgical therapy in the management of the acute stages of unstable angina pectoris. To date 150 patients have been included in the randomized trial, 80 assigned to medical and 70 to surgical therapy; the clinical presentation, coronary arterial anatomy and left ventricular function in the two groups are similar. Some physicians have been reluctant to prescribe medical or surgical therapy by a random process, and the ethical basis of the trial has been questioned. Since there are no hard data regarding the natural history and outcome of therapy for unstable angina pectoris, randomization appears to provide a rational way of selecting therapy. Furthermore, subsets of patients at high risk may emerge during the process of randomization. The design of this randomized trial is compared with that of another reported trial. Thus far, the study has shown that it is possible to conduct a randomized trial in patients with unstable angina pectoris, and that the medical and surgical groups have been similar in relation to the variables examined. The group as a whole presented with severe angina pectoris, either as a crescendo pattern or as new onset of angina at rest, and 84 percent had recurrence of pain while in the coronary care unit and receiving vigorous medical therapy. It is anticipated that sufficient patients will have been entered into the trial within the next 12 months to determine whether medical or surgical therapy is superior in the acute stages of unstable angina pectoris.

Mid-ventricular obstruction: a variant of obstructive cardiomyopathy.

In two patients with clinical and catheterization findings of hypertrophic obstructive cardiomyopathy, the level of intraventricular obstruction was found to be in the mid-ventricular area rather than at the junction of the inflow and outflow tracts. One patient died suddenly shortly after unsuccessful outflow tract myectomy. In vivo recognition of this probably rare variant form of obstructive cardiomyopathy rests mainly on the angiograhic appearance of the left ventricle and on the recording of pressures in multiple sites of the left ventricular cavity. Surgical relief of the obstruction in these patients is not likely to be obtained by a transaortic left ventricular outflow myectomy but may require either papillary muscle resection by the transatrial or transventricular approach or mid-ventricular septectomy, or both.

Relationship of the Pulmonary Artery End-Diastolic Pressure to the Left Ventricular End-Diastolic and Mean Filling Pressures in Patients With and Without Left Ventricular Dysfunction

The relationship of the left ventricular end-diastolic pressure (LVEDP) and the pulmonary arterial “wedge” mean pressure (PAWMP) to the pulmonary artery end-diastolic pressure (PAEDP) was investigated by cardiac catheterization in 71 subjects. Pressure records were obtained simultaneously or immediately consecutively. In 15 subjects with normal LV function (LVEDP, 4 to 12 mm Hg) PAEDP was within 3 mm Hg of LVEDP (r = 0.70, P < 0.01) and within 3 mm Hg of PAWMP (r = 0.69, P < 0.01) in every instance.In 56 patients with LV dysfunction (LVEDP, 12 to 55 mm Hg), PAEDP was lower than LVEDP in 42, equal to LVEDP in six, and higher than the LVEDP in eight, who were in atrial fibrillation or had increased pulmonary vascular resistance (PVR). PAEDP correlated closely with PAWMP (r = 0.92, P < 0.001).In 30 patients with LV dysfunction in sinus rhythm, an a wave was identified in the PA pressure tracing (PA a) prior to systole which coincided in time and magnitude to the PAW a wave and was considered to represent retrograde transmission of the left atrial contraction wave. The PA a pressure was within 5 mm Hg of the LVEDP (r = 0.94, P < 0.001) in all except four patients, two of whom had elevated PVR.Thus, in the presence of LV dysfunction and elevated LVEDP, PAEDP correlated well with PAWMP, but failed to represent LVEDP accurately, while PA a wave pressure closely reflected LVEDP except when PVR was markedly increased.

Unstable angina pectoris: National cooperative study group to compare medical and surgical therapy. I. Report of protocol and patient population

A preliminary report is presented of a prospective randomized trial conducted by eight cooperative institutions under the auspices of the National Heart and Lung Institute to compare the effectiveness of medical and surgical therapy in the management of the acute stages of unstable angina pectoris. To date 150 patients have been included in the randomized trial, 80 assigned to medical and 70 to surgical therapy; the clinical presentation, coronary arterial anatomy and left ventricular function in the two groups are similar. Some physicians have been reluctant to prescribe medical or surgical therapy by a random process, and the eithical basis of the trial has been questioned. Since there are no hard data regarding the natural history and outcome of therapy for unstable angina pectoris, randomization appears to provide a rational way of selecting therapy. Furthermore, subsets of patients at high risk may emerge during the process of randomization. The design of this randomized trial is compared with that of another reported trial. Thus far, the study has shown that it is possible to conduct a randomized trial in patients with unstable angina pectoris, and that the medical and surgical groups have been similar in relation to the variables examined. The group as a whole presented with severe angina pectoris, either as a crescendo pattern or as new onset of angina at rest, and 84 percent had recurrence of pain while in the coronary care unit and receiving vigorous medical therapy. It is anticipated that sufficient patients will have been entered into the trial within the next 12 months to determine whether medical or surgical therapy is superior in the acute stages of unstable angina pectoris.Abstract A preliminary report is presented of a prospective randomized trial conducted by eight cooperative institutions under the auspices of the National Heart and Lung Institute to compare the effectiveness of medical and surgical therapy in the management of the acute stages of unstable angina pectoris. To date 150 patients have been included in the randomized trial, 80 assigned to medical and 70 to surgical therapy; the clinical presentation, coronary arterial anatomy and left ventricular function in the two groups are similar. Some physicians have been reluctant to prescribe medical or surgical therapy by a random process, and the ethical basis of the trial has been questioned. Since there are no hard data regarding the natural history and outcome of therapy for unstable angina pectoris, randomization appears to provide a rational way of selecting therapy. Furthermore, subsets of patients at high risk may emerge during the process of randomization. The design of this randomized trial is compared with that of another reported trial. Thus far, the study has shown that it is possible to conduct a randomized trial in patients with unstable angina pectoris, and that the medical and surgical groups have been similar in relation to the variables examined. The group as a whole presented with severe angina pectoris, either as a crescendo pattern or as new onset of angina at rest, and 84 percent had recurrence of pain while in the coronary care unit and receiving vigorous medical therapy. It is anticipated that sufficient patients will have been entered into the trial within the next 12 months to determine whether medical or surgical therapy is superior in the acute stages of unstable angina pectoris.

Unstable angina pectoris: National cooperative study group to compare surgical and medical therapy: III. Results in patients with S-T segment elevation during pain

Abstract A prospective randomized study comparing intensive medical therapy with urgent coronary bypass surgery for the acute management of patients with unstable angina pectoris was carried out by nine cooperating medical centers under the auspices of the National Heart, Lung, and Blood Institute. Between 1972 and 1976, a total of 288 patients were entered into the study; 79 of these (27 percent of the total study group) with 70 percent or more fixed obstruction in one or more coronary arteries had episodes of pain at rest associated with transient S-T segment elevation. Forty-two were randomized to medical and 37 to surgical therapy. The hospital mortality rate was 4.8 percent for the medical and 5.4 percent for the surgical group (difference not significant). The rate Of in-hospital myocardial infarction was 12 percent in the medical and 14 percent in the surgical group (difference not significant). During the 1st and 2nd years of follow-up, 25 percent in the medical and 15 percent in the surgical group complained of New York Heart Association class III or IV angina (difference not significant). During an average follow-up period of 42 months 45 percent of the medically treated patients later underwent surgery to relieve unacceptable angina. In the medical group 65 percent were working full- or part-time at the end of 1 year and 61 percent at the end of 2 years of follow-up; comparable figures for the surgically treated group were 63 and 68 percent. The results indicate that patients with unstable angina pectoris with transient S-T segment elevation during pain at rest with fixed obstruction of 70 percent or more in one or more coronary arteries do not differ significantly from patients with pain at rest associated with transient S-T segment depression or T wave inversion. The condition of such patients can be stabilized, and they can be managed with a maximal medical program including propranolol and long-acting nitrates in pharmacologic doses with good control of pain in most and no increase in rate of early mortality or myocardial infarction. Later, elective surgery can be performed with a lower risk and good clinical results if the patients angina fails to respond to intensive medical therapy.

The effects of dopamine on depressed myocardial function following coronary embolization in the closed-chest dog

Severe myocardial depression was induced in 12 anesthetized closed-chest dogs by mercury embolization of the left coronary artery and the effects of dopamine infusion (5 μg per kilogram per minute) studied. Coronary embolization produced decreases in cardiac output (CO) of 52 per cent, stroke volume (SV) of 49 per cent, left ventricular peak dPdt (LVdPdt) of 29 per cent, stroke work (SW) of 60 per per cent, LV systolic pressure (LVSP) of 14 per cent, and an increase in systemic vascular resistance (SVR) of 77 per cent. LV end-diastolic pressure (LVEDP) increased from 7 to 18 mm. Hg. After 20 minutes of dopamine, CO increased 30 per cent, SV 31 per cent, SW 46 per cent, LVdPdt 64 per cent, and LVSP 8 per cent; SVR decreased 18 per cent and LVEDP was 14 mm. Hg (all changes p < 0.05). Heart rate and mean aortic pressure did not change. After 60 minutes of dopamine, slight deterioration occurred but most parameters were still significantly improved. Thirty minutes after stopping dopamine, marked circulatory deterioration recurred. Persistent ventricular dysrhythmias occurred in 6 dogs, in 4 of whom dopamine dosage had to be decreased to 2.2 μg per kilogram per minute because of persistent ventricular tachycardia. It is concluded that dopamine will improve depressed myocardial function following acute coronary arterial embolization, at least temporarily, but that the incidence of serious ventricular dysrhythmias may well limit its use.

Progressive Pulmonary Vascular Obstruction and Cor Pulmonale Due to Repeated Embolism from Axillary Vein Thrombosis

Abstract A case of posttraumatic axillary vein thrombosis in an otherwise healthy young man gave rise to rapidly progressive obstructive pulmonary hypertension, a result of recurrent thromboembolis...

The effects of coupled and paired ventricular stimulation following acute myocardial infarction in dogs.

Abstract Circulatory depression was produced in 10 anesthetized dogs following left coronary embolization with mercury. Marked decreases in cardiac output and LV dp/dt and significant increases in systemic vascular resistance and left ventricular end-diastolic pressure were observed. Systemic arterial pressure decreased only moderately. Coupled and paired ventricular stimulation both resulted in significant increases in LV dp/dt, stroke volume, and stroke work, but cardiac output, LV end-diastolic pressure, and systemic vascular resistance remained unchanged. Ventricular fibrillation occurred in one instance during coupled ventricular stimulation and in 6 instances during paired ventricular stimulation. It is concluded that neither coupled nor paired ventricular stimulation provides significant hemodynamic benefit to the depressed circulatory state following coronary embolization in the dog. Furthermore, the high incidence of ventricular fibrillation contraindicates the use of paired ventricular stimulation during acute myocardial ischemia. Coupled ventricular stimulation may have a beneficial effect when disproportionate tachycardia is present.

Circulatory Effects of Carotid Sinus Nerve Stimulation in Dogs with Reference to Coronary Flow and Resistance

The effects of electrical stimulation of the carotid sinus nerves upon heart rate, myocardial function, circulatory dynamics, and coronary flow were studied in the anesthetized, open-chest dog. Carotid sinus nerve stimulation produced a transient profound bradycardia, which was abolished by vagotomy, and a more sustained, less marked, slowing of the heart, which became less marked after propranolol. The effects on cardiac output were variable. Significant drops in aortic pressure and systemic resistance were observed. Anterior descending coronary arterial flow also decreased significantly, but the changes in calculated coronary vascular resistance were variable. A disproportionate reduction in coronary blood flow was observed relative to the decrease in myocardial oxygen consumption. Under the conditions of our experiment, carotid sinus nerve stimulation significantly decreased cardiac work, arterial pressure, and myocardial contractility, and probably produced some coronary vasoconstriction secondary to the reduction in myocardial oxygen demand.