Radionuclide-guided balloon occlusion pulmonary cineangiography: an adjunct to pulmonary arteriography.

Fifty-eight patients, 38 of whom had pulmonary emboli, were evaluated for pulmonary occlusive disease with flow-directed balloon occlusion pulmonary cineangiography. Areas studied were selected by radionuclide perfusion lung scans and indeterminant areas of pulmonary occlusion were imaged on standard catheter pulmonary magnification cut films. In 4 of 38 patients, the balloon occlusion technique demonstrated peripheral pulmonary emboli not seen on standard pulmonary arteriography. Selective flow-directed balloon occlusion pulmonary cineangiography is an effective adjunct for evaluating some patients with pulmonary emboli.

Reevaluation of electrocardiographic criteria for left, right and combined cardiac ventricular hypertrophy.

Cardiac chamber weight was determined at necropsy in 323 men to develop correlative studies of electrocardiographic criteria for ventricular hypertrophy. Thirty recommended criteria for left ventricular (LV) hypertrophy, 10 for right ventricular (RV) hypertrophy, and combinations of both criteria for combined hypertrophy were evaluated. Four methods for electrocardiographic diagnosis of LV hypertrophy were derived: (1) a modification of the Romhilt-Estes point system; (2) the presence of any 1 of 3 criteria: (a) S V1 + R V5 or V6 greater than 35 mm, (b) left atrial abnormality, or (c) intrinsicoid deflection in lead V5 or V6 greater than or equal to 0.05 second; (3) a combination of any 2 criteria or of 1 criterion (above) plus at least 1 of the following 3 additional criteria: (a) left-axis deviation greater than -30 degrees, (b) QRS duration greater than 0.09 second, or (c) T-wave inversion in lead V6 of 1 mm or more; and (4) the use of a single criterion--left atrial abnormality. Sensitivity varied from 57 to 66% and specificity from 85 to 93% among these 4 methods. Myocardial infarction increased sensitivity of the foregoing methods, but the specificity was reduced. Method 2 is preferred for the electrocardiographic diagnosis of LV hypertrophy. Two methods were useful for right ventricular (RV) hypertrophy: (1) the use of any 1 of 4 criteria: (a) R/S ratio in lead V5 or V6 less than or equal to 1; (b) S V5 or V6 greater than or equal to 7 mm; (c) right-axis deviation of more than +90 degrees, or (d) P pulmonale; and (2) use of any 2 combinations of the foregoing criteria. Sensitivity ranged from 18 to 43% and specificity from 83 to 95%. Combined hypertrophy was best diagnosed using left atrial abnormality as the sole criteria of LV hypertrophy, plus any 1 of 3 criteria of RV hypertrophy: (a) R/S ratio in lead V5 or V6 less than or equal to 1, (b) S V5 or V6 greater than or equal to 7 mm, or (c) right axis deviation greater than +90 degrees.(ABSTRACT TRUNCATED AT 250 WORDS)

Electrocardiographic changes with coronary artery spasm.

The presence or absence of important ECG changes (e.g., ST elevation or depression greater than or equal to 1 mm) was evaluated in 79 consecutive patients with coronary artery spasm. In eight of these patients ECG changes usually did not accompany episodes of rest angina. Evaluation before, during, and after cardiac catheterization included multiple ECGs and ambulatory monitoring during angina. Our observations suggest that the ECG may not always be a sensitive indicator of coronary spasm. Thus the diagnosis of transient myocardial ischemia secondary to coronary spasm should not necessarily be excluded because of a lack of ECG changes during rest angina.

Digitalis-sensitive Na+, K+-ATPase: lack of a direct catecholamine-mediated stimulation in bovine myocardial tissue.

It has been documented that biogenic amines can stimulate Na+, K+-ATPase from various tissue preparations. However, it is unclear whether or not this stimulation occurs in myocardial tissues. We have evaluated possible catecholamine stimulation of purified Na+, K+- ATPase preparations utilizing a bovine ventricular microsomal preparation. We have studied the dose response of the enzyme to ouabain and digitoxigenin in the presence and absence of propranolol and norepinephrine. Our results indicate that propranolol increases the sensitivity of Na+, K+-ATPase to inhibition by digitalis, and that stimulation of Na+, K+-ATPase in bovine myocardium is not mediated via an adrenergic mechanism. In addition, our results indicate that in myocardial tissue, both stereoisomers of propranolol produce a direct nonspecific membrane effect which can modify Na+, K+-ATPase activity.

Regional coronary hemodynamic responses to cold stimulation in patients without variant angina.

The responses to cold in patients with exertional chest pain were studied by measuring coronary sinus and great cardiac vein flows, aortic and left ventricular pressure and diameters of epicardial and small (0.4 to 1.0 mm) intramyocardial coronary arteries before and after the left hand of 18 such patients was immersed in ice water. Coronary sinus and great cardiac vein flows were used as indexes of total and anterior left ventricular flows. Coronary sinus flow minus great cardiac vein flow was used as an index of inferior left ventricular flow. Perfusion of left ventricular regions was considered potentially "normal" or "abnormal" according to the presence or absence of 50 percent or greater stenosis of luminal diameter in the coronary artery supplying a given region. With cold stimulation, increases occurred in heart rate (6 beats/min), mean aortic pressure (22 mm Hg) and left ventricular end-diastolic pressure (8 mm Hg) (all p less than 0.05). Left ventricular flow in normally perfused regions increased as resistance decreased. Left ventricular flow in abnormally perfused regions increased slightly and resistance increased. Regional left ventricular flow increased more, and changes in resistance differed in normally and abnormally perfused regions. Coronary arterial diameter decreased only minimally (6 percent) in both normal and abnormal left ventricular regions. These data show that cold stimulation increases coronary resistance in abnormally perfused left ventricular regions. Cold stimulation-related increases in coronary resistance do not appear to be caused by coronary arterial "spasm."

Variability of electrocardiographic responses to repeated ergonovine provocation in variant angina patients with coronary artery spasm.

We reviewed our experience with serial ergonovine provocative tests for coronary artery spasm (CAS) in ten variant angina patients with angiographically proved CAS. Of the 26 ergonovine tests performed in the ten patients, only four patients exhibited reproducible ECG response to ergonovine. The remaining six patients had variable and unpredictable ECG responses to ergonovine. All patients were in an active phase of their disease. The variability of ST segment directional response to ergonovine is considered to be on the basis of disparate sensitivity of the coronary circulation to intravenous ergonovine. Because of this variable response, the ECG response alone should not be considered as the standard indicator for CAS presence but should be utilized with other hemodynamic and angiographic criteria.

Regional coronary angiographic observations during cold stimulation in patient with exertional chest pain: comparison of diameter responses in normal and fixed stenotic vessels.

In 12 patients with exertional chest pain, coronary angiography was performed and quantitative measurements coronary artery (CA) diameters were made before and during cold stimulation (four normal CA patients and eight fixed CA stenosis patients). The left main CA; proximal, middle and distal anterior descending and circumflex segments; and small intramyocardial CAs (0.4 to 1.0 mm) usually showed only minimal and similar degree of vasoconstriction (average diameter reduction 6%) during cold stimulation in both normals and CA disease (CAD) patients. Magnitude of vasoconstriction differed among some CA segments measured; the left main CA segment (0 +/- 2%, mean +/- SD) usually did not change while distal segments (-10 +/- 10%) usually demonstrated greatest percentage vasoconstriction. Coronary stenoses and CAs filled by collaterals did not demonstrate increased magnitude of vasoconstriction compared to other CAs. Results of other CA segments were also similar comparing patients with and without CAD. The minimal degree of vasoconstriction observed in these CA segments does not appear to account for the large increase in coronary resistance reported during cold stimulation in CAD patients.

Thermoregulatory failure secondary to acute illness: complications and treatment.

We report on six patients in whom hypothermia secondary to acute illnesses, including pneumonia, congestive heart failure, renal failure, drug overdose, and hypoglycemia, developed. Complications that occurred were metabolic acidosis in six patients, altered sensorium in five, bradyarrhythmia in three, and hyperamylasemia in two. All patients failed to demonstrate a shivering response and represent cases of acute thermoregulatory failure. Five of the six patients survived. In the course of treatment, the choice of active or passive rewarming should be based on whether or not normal thermoregulatory mechanisms are intact.