PubMed HealthSearch

Biomedical subjects

L Gould

Publications and source records attributed to L Gould.

At least 19 recordsLinked to original sources

Electrophysiologic properties of coffee in man.

There is no information on the effects of coffee on the human conduction system. His bundle electrograms were obtained in 12 patients before and 20 minutes after the ingestion of coffee containing 150 mg caffeine. Antegrade and retrograde refractory periods were obtained with the extrastimulus method. The effective and functional refractory period of the atrioventricular node decreased after coffee ingestion. This improvement in conduction is probably mediated by a release of catecholamines.

Adult

Inappropriate slowing of the pacemaker rate with programmable demand pacemaker.

A 60-year-old male with a programmable pacemaker developed inappropriate slowing of the pacemaker rate. This was due to oversensing of the T waves combined with after-potential sensing. This does not represent generator malfunction and can usually be corrected by reprogramming the pulse duration, or the milliamperage.

Electrocardiography

His bundle electrogram in patients with acute myocardial infarction.

Thirty-seven patients with acute myocardial infarction complicated by atrioventricular or bundle branch block, or a combination of both, has His bundle electrogram studies performed during their stay in the coronary care unit. The acute mortality of the 14 patients with a complicating bundle branch was 50%. Pump failure was the main cause of death. Three patients in this group had a prolonged H-V interval and one patient had a split blundle of His. The presence or absence of a prolonged H-V interval did not affect mortality in this group of patients. The acute mortality of the 16 patients with an inferior wall myocardial infarction was 6%. The H-V interval was normal in all but one of these patients. The atrioventricular block was caused by a proximal block in all cases. The acute mortality of the seven patients with an anterior wall myocardial infarction was 29%. The H-V interval was prolonged in two of seven patients. Pump failure was the acute cause of the deaths. The presence or absence of a prolonged H-V interval did not affect mortality in this group of patients.

Adult

Decline of serum phosphorus in acute myocardial infarction.

Levels of serum calcium, phosphorus, magnesium, SGOT, CPK, and LDH were measured in 61 patients admitted to a coronary care unit. In 34 the ECG and enzymes confirmed an acute myocardial infarction, whereas the remaining 27 did not have an acute myocardial infarction. The serum phosphorus declined significantly in those with the acute infarction compared to the control group. The fall was most marked in the third and fourth postinfarction day, and by the fifth day had returned to baseline values. The serum calcium and magnesium did not change significantly over the 5 days. Thus the fall in the serum phosphorus serves as a sensitive indicator of acute myocardial infarction.

Acute Disease

Hemodynamic effects of phentolamine in mitral stenosis and congestive cardiomyopahty.

Nine patients with alcoholic cardiomyopathy and 8 patients with mitral stenosis were studied by right and left heart catheterization. Hemodynamic observations were made during control period and during the infusion of phentolamine at a rate of 0.3 mg per minute. The patients with the cardiomyopathy responded to phentolamine with a significant decline in the left ventricular filling pressure, pulmonary artery mean pressure, peripheral resistance, and arteriovenous oxygen difference. There was a significant increase in the cardiac index. The patients with mitral stenosis did not show any hemodynamic improvement after phentolamine infusion.

Cardiac Output

Electrophysiologic properties of nitroprusside in man.

The effects of nitroprusside on His bundle electrograms, when given intravenously for 10 minutes, were studied in 14 patients with heart disease. Recordings were made at varied heart rates using atrial and ventricular pacing. Nitroprusside significantly reduced the AH interval, but it had no effect on the HV interval. Functional and effective refractory periods were measured by the extrastimulus technique. The functional refractory period of the AV node as well as the effective refractory period of the ventriculoatrial conduction system significantly decreased after nitroprusside infusion. This improvement in conduction can probably be explained by the systemic hypotension produced by nitroprusside, which reflexly will increase sympathetic drive to the heart and decrease vagal tone.

Adult

Electrophysiologic properties of methyldopa in man.

There is little information on the effects of methyldopa on the human conduction system. His bundle ECGs were obtained in 11 patients before and after the intravenous infusion of 100 mg of methyldopa. Antegrade refractory periods were obtained with the extrastimulus method. The significant results were as follows: the sinus rate was 71 +/- 4 beats per minute before, and 65 +/- 3 beats per minute after methyldopa (P less than 0.01). The mean A-H interval at a paced rate of 120 beats per minute was 113 +/- 14 msec before, and 135 +/- 18 msec after, methyldopa (P less than 0.05). The mean atrioventricular nodal functional refractory period was 430 +/- 23 msec before and 452 +/- 24 msec after methyldopa administration (P less than 0.001). The mean effective refractory period was 385 +/- 29 msec before, and 388 +/- 27 msec after methyldopa (P less than 0.01). The sinus node recovery time in the control state was 989 +/- 55 msec and 1102 +/- 66 msec after methyldopa infusion (P less than 0.05). Thus, methyldopa can impair conduction through the atrioventricular node and depress the sinus node.

Adult

Pericardial effusion as an early complication of acute myocardial infarction.

Two days after an acute myocardial infarction, a patient developed pleuropericarditis. A negative lung scan and echocardiographic evidence of pericardial effusion were instrumental in making the diagnosis. Steroid therapy led to a dramatic resolution of the signs and symptoms. Pericardial effusion is usually a late complication of myocardial infarction (Dressler's syndrome), but the increasing use of echocardiography may demonstrate that it occurs early in the course.

Acute Disease

Pancreatic pseudocyst simulating an intrahepatic mass.

A case of pancreatic pseudocyst is presented which mimicked an intrahepatic mass both after selective hepatic arteriography and isotope (99m Tc-S-Co) evaluation of the liver. A previous upper gastrointestinal series and ultrasonograhpy had seemed to accurately establish the diagnosis of pancreatic pseudocyst. A pancreatic pseudocyst may pose as an intrahepatic mass lesion and this entity should be recognized as a pitfall in nuclear imaging of the liver.

Adult

Hemodynamic effects of morphine in cardiac disease.

The hemodynamic effects of intravenous morphine were documented by right heart catheterization in six patients with an acute uncomplicated transmural myocardial infarction one to three days after the onset of symptoms. Intracardiac pressures, brachial artery pressure, and cardiac output were determined before and 15 minutes after the termination of the morphine infusion. Five milligrams morphine was given intravenously over a 10-minute period. The brachial artery pressure fell from a mean of 78 to a mean of 73 mm Hg (NS). As a result or morphine administration, the average cardiac index decreased from 2.68 to 2.31 liters/min-m2 (P is less than 0.05), and the stroke index decreased from 27 to 22 ml/beat-m2 (P is less than 0.05). Only small changes were observed in the intracardiac pressures.

Adult

The sick sinus syndrome. A study of 50 cases.

The long term prognosis was studied in 50 patients treated for the sick sinus syndrome with pacemaker insertion. The mean age of the patients was 71 years. There were 31 females and 19 males in the series. Nine patients (18%) died during the average follow-up period of 19 months. Dizzy and syncopal episodes were abolished in most patients with pacemaker therapy. However only two of the nine patients in congestive heart failure improved with the pacemaker. Thus the long term prognosis of patients with the sick sinus syndrome is poor despite pacemaker therapy. This is particularly true for the patient in chronic congestive heart failure who does not respond to the pacemaker treatment.

Adult

The effect of phentolamine on intra-Hisian conduction.

A His bundle electrogram was obtained in a 70 year old male with syncopal episodes. A split bundle of His deflection was recorded. After the intravenous administration of phentolamine, a marked shortening of the H-H' interval was observed. This signifies an improvement in conduction at the bundle of His level.

Action Potentials

Severe mitral regurgitation with a normal-sized left atrium.

The syndrome of severe mitral regurgitation with a normal-sized left atrium may or may not be associated with pulmonary hypertension and prominent left atrial V waves. To explain these pressure alterations by a single pressure-volume relationship is probably not adequate. It would appear that, whatever the clinical circumstances, normal pulmonary vascular pressures cannot exclude the diagnosis of mitral regurgitation.

Adult