No abstract

The purpose of this study was to determine the effect of smoking marihuana and of high-nicotine cigarettes on exercise-induced angina pectoris. Smoking 1 marihuana cigarette increased the resting product of systolic blood pressure times heart rate 54%, increased the venous carboxyhemoglobin level, and decreased the exercise time until angina 50% in 10 patients with angina pectoris. Smoking 1 high-nicotine cigarette increased the resting product of systolic blood pressure times heart rate 36%, increased the venous carboxyhemoglobin level, and decreased the exercise time until angina 23%. Smoking either marihuana or high-nicotine cigarettes decreases exercise performance until angina by increasing myocardial oxygen demand and by decreasing myocardial oxygen delivery. Smoking 1 marihuana cigarette decreased the exercise time until angina more than smoking 1 high-nicotine cigarette (p less than 0.001).

Smoking high-nicotine cigarettes caused a significant increase in systolic and diastolic arterial pressure, heart rate, left ventricular end-diastolic pressure, and coronary sinus, arterial, and venous CO levels, no significant change in left ventricular dp/dt, aortic systolic ejection period, and cardiac index, and a significant decrease in stroke index and coronary sinus, arterial, and venous P02 levels in eight anginal patients with documented coronary disease. One week later, these patients inhaled 150 ppm of carbon monoxide until their increase in coronary sinus CO was similar to that produced after smoking their third cigarette. Inhaling carbon monoxide caused a significant increase in left ventricular end-diastolic pressure and coronary sinus, arterial, and venous CO levels, no significant change in systolic and diastolic arterial pressure, heart rate, and systolic ejection period, and a significant decrease in left ventricular dp/dt, stroke index, cardiac index, and coronary sinus, arterial, and venous PO2 levels. Nicotine caused the increased systolic and diastolic arterial pressure and heart rate after smoking. Carbon monoxide caused the negative inotropic effect which increased the left ventricular end-diastolic pressure and decreased the stroke index after smoking.

SUMMARYOne hundred patients with angina and 100 normal subjects, mean age 51 years, had simultaneous phonocardiograms and electrocardiograms at rest and after a double Mas-ter's test. A fourth heart sound was present at rest in 43% of the patients and 14% of the normal subjects, and after exercise in 94% of the patients and 29% of the normal subjects. All patients and the normal subject who had a third heart sound at rest had a fourth heart sound at rest, and all who had a third heart sound after exercise had a fourth heart sound after exercise. Fifty-nine per cent of the patients and 4% of the normal subjects had an ST-segment shift .1.0 mm, and 67% of the patients and 6% of the normal subjects had an ST-segment shift .0.5 mm. After exercise, 97% of the patients and 30% of the normal subjects had a fourth heart sound or an ST-segment shift .0.5 mm. Additional Indexing Words: ExerciseCoronary heart disease Third heart sound Fourth heart sound FOURTH and third heart sounds may occur in ischemic heart disease. We performed this study to determine the incidence of phonocardiographically recorded fourth and third heart sounds before and after a double Master's two-step test in patients with angina pectoris due to coronary artery disease and in normal subjects. XLIII, February 1971 98 men and two women, between the ages of 37 and 64 years, with a mean age of 51 ± 6. The normal subjects included 98 men and two women, between the ages of 38 and 64 years, with a mean age of 51 ± 6. The normal subjects were hospital personnel or their friends. All of the normal subjects had blood pressures below 140/90 mm Hg, and none of them were on any medication. Twenty-seven of the patients with angina pectoris had coronary artery disease documented by previous coronary angiography, with 50% or greater narrowing of the lumen of at least one major vessel. The other 73 patients with angina pectoris had a documented transmural myocardial infarction at least 6 months old, with evolution of abnormal Q waves on serial electrocardiograms.None of the patients with angina had A-V block, bundle branch block, valvular heart disease, a myocardiopathy, a high cardiac output state, or a blood pressure above 150/98 mm Hg. None of these patients were on diuretics or digitalis within 3 weeks of this study; none were on quinidine or procainamide within 3 days of this study; none were on antianginal drugs except for nitroglycerin within 3 days of this study; and none were on nitroglycerin on the day of this study.

The double Master's test, the maximal treadmill stress test, the resting apexcardiogram, and the postexercise apexcardiogram significantly correlated with the development of subsequent coronary heart disease within five years in 100 asymptomatic persons. The maximal treadmill stress test correlated better than the double Master's test in predicting subsequent coronary heart disease. The presence of both an abnormal maximal treadmill stress and an abnormal a-wave ratio in the postexercise apexcardiogram had the best value in predicting subsequent coronary heart disease.