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Biomedical subjects

R F Lewin

Publications and source records attributed to R F Lewin.

At least 55 records · Page 3Linked to original sources
PubMed1986

The brachial artery method to transluminal internal mammary artery angioplasty.

A new catheter technique to perform angioplasty of the right or left internal mammary artery coronary graft utilizing the brachial artery approach is described. Utilization of the ipsilateral brachial artery permitted cannulation of the internal mammary artery with preformed polyurethane Teflon-lined guide catheters. The coronary dilatation catheter was passed through the guiding catheter into the internal mammary artery. This technique permitted successful access into the ipsilateral mammary artery in eight patients, the left internal mammary artery graft in five and the right in three patients. The angioplasty procedure was successfully performed in seven of eight cases (spasm of the left internal mammary artery precluded successful dilatation catheter passage in one case). No brachial artery complications were encountered. In two cases, angioplasty was successfully performed in additional coronary vessels. Follow-up of 1-16 months (mean: 7.7 months) revealed no clinical evidence of restenosis. The ipsilateral brachial artery approach utilizing preshaped guiding catheters for visualization and introduction of dilatation catheters into the internal mammary artery graft is a safe and successful approach, and it is an acceptable alternative to the femoral technique.

Adult↗
PubMed1986

Unstable angina pectoris evolving to acute myocardial infarction: significance of ECG changes during chest pain.

We retrospectively evaluated 32 patients with unstable angina (UA) and no evidence of increased oxygen demand during episodes of chest pain (no significant changes in heart rate and blood pressure), who developed an acute myocardial infarction (AMI) during the same hospitalization. Based on the type of ST changes during anginal pain, two groups were defined: Group A included 19 patients who developed ST elevation during AMI; 15 of these 19 patients (79%) were in Killip class I, two were in class II, and there was one patient each in classes III and IV, respectively. Only one of the 19 patients died. Group B included 13 patients who developed ST depression during AMI; nine of these 13 patients were in Killip class IV and the remaining four patients died before they could be evaluated. Ten patients died (77%) (p less than 0.01), seven in electromechanical dissociation and three in cardiogenic shock. Postmortem examination, performed in four patients, revealed total obstruction of the left main coronary artery. It is concluded that patients with UA who, during attacks of chest pain, develop ST depression and no evidence of increased oxygen demand may have a poor prognosis when they develop an AMI. This selected group of high-risk patients appears to need immediate intensive medical care and most probably early surgical treatment.

Adolescent↗
PubMed1986

Unstable angina: the significance of ST segment elevation or depression in patients without evidence of increased myocardial oxygen demand.

We evaluated 46 patients with unstable angina (UA), who showed no significant changes in heart rate, blood pressure, and double product (as evidence of increased oxygen demand) during episodes of chest pain. Coronary angiography was performed in all patients during the same hospitalization. Of 26 patients with UA and ST depression (group A), 10 had left main coronary artery disease (CAD) and eight had left main equivalent CAD. Of 20 patients with UA and ST elevation (group B), only one had left main CAD and one had left main equivalent CAD. All patients in group A had ST depression in leads V4 and V5, and all patients in group B had ST elevation in leads V2 and V3. The presence of ST depression in leads V4 and V5 in UA patients without evidence of increased oxygen demand may be suggestive of significant left main or left main equivalent CAD. Therefore, coronary angiography is recommended during the same hospitalization.

Adult↗
PubMed1986

Transient right axis deviation during acute anterior wall infarction or ischemia: electrocardiographic and angiographic correlation.

Eleven patients, three with acute anterior myocardial infarction and eight with anterior ischemia, who developed transient right axis deviation with a left posterior hemiblock pattern during the acute phase of myocardial infarction or ischemia are described (study group). A correlation between their electrocardiographic pattern and the angiographic findings was made. The arteriographic findings were compared with those of a group of 24 patients with acute anterior myocardial infarction or ischemia without transient right axis deviation (control group). The main electrocardiographic characteristics of the right axis deviation pattern were: an average shift of the mean frontal axis to the right of 42 degrees (10 degrees to 94 degrees); increased voltage of R waves in leads II, III and a VF and appearance of small Q waves or decreased voltage of Q waves if previously present in the same leads; decreased voltage of R waves and appearance of deep S waves in lead aVL; and inverted T waves and isoelectric ST segments in leads II, III and aVF. Coronary angiography revealed that the study group had a higher incidence of significant right coronary artery obstruction and collateral circulation between the left coronary system and the posterior descending artery than did the control group (100 versus 25% and 73 versus 0%, respectively; p less than 0.01). There were no differences between the groups regarding left anterior descending and circumflex artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Predominant right ventricular infarction. Clinical and electrocardiographic features.

Based on two-dimensional echocardiographic wall motion abnormalities, 82 patients with acute inferior wall myocardial infarction were divided into 3 groups: group 1. predominant right ventricular infarction-20 patients; group 2. combined right and left ventricular infarction-33 patients; and group 3. predominant left ventricular infarction-29 patients. There were no significant statistical differences between the three groups regarding age, sex, Killip class on admission and jugular venous engorgement. Group 2 patients had higher peak creatine kinase levels and a lower rate of life threatening ventricular arrhythmia than the other groups. On M-mode echo, patients in group 1 had higher RV/LV ratios and lower left ventricular systolic and diastolic dimensions than group 3 patients. On 2-D echo and radionuclear studies, group 1 patients had more right ventricular wall motion abnormalities and minimal left ventricular wall motion disturbances. The left ventricular ejection fraction was higher and the right ventricular ejection fraction lower in group 1 patients than in those groups 2 and 3. The electrocardiogram showed small Q and relatively tall R waves in II, III, AVF in group 1 patients, and deep Q with loss of R waves in patients with combined or exclusive left ventricular infarction (groups 2 and 3). We conclude that predominant right ventricular infarction, which occurs in 24% of inferior wall infarction patients cannot be characterized clinically; however, an electrocardiographic pattern was found to detect this form of infarction with a sensitivity of 80% and a specificity of 70%. Combined left and right ventricular infarction and exclusive left ventricular infarction could be detected electrocardiographically with a sensitivity of 70% and a specificity of only 30%.

Aged↗
PubMed1986

Alternating Wenckebach periods in acute inferior myocardial infarction: clinical, electrocardiographic, and therapeutic characterization.

We report on twelve patients with alternating Wenckebach periods (AWP) occurring during an acute inferior myocardial infarction (AIMI). There were nine males and three females, with a mean age of 61 years (range, 43 to 75). AWP appeared during the first 48 hours of the AIMI in 10 patients and on the fourth day of hospitalization in two patients. AWP occurred spontaneously in nine patients and following the administration of atropine in the remaining three patients. Mean systolic blood pressure significantly decreased during AWP as compared to the period preceding or following the bradyarrhythmia (93 +/- 42 mmHg vs 123 +/- 37 mmHg, p less than 0.02). Killip functional class was significantly higher during AWP as compared to the period preceding or following the bradyarrhythmia (2.1 +/- 1.2 vs 1.5 +/- 0.8, p less than 0.02). Pacemaker therapy was initiated prophylactically in two patients, because of syncope in six, because of hemodynamic deterioration in two, and for syncope and hemodynamic deterioration in two. Three patients died in cardiogenic shock despite pacemaker therapy. No evidence of right ventricular infarction was seen in the patients. Atropine administration during AWP significantly increased the sinus rate and significantly decreased the ventricular rates and the systolic blood pressure. In addition, three patients developed long bouts of paroxysmal AV block. Isoproterenol administration improved AV conduction in one patient, caused no change in two patients and induced non-sustained ventricular tachycardia in three patients. In conclusion, AWP occurring during AIMI is a symptomatic bradyarrhythmia associated with hemodynamic deterioration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Polymorphous ventricular tachycardia and atrioventricular block.

Nine patients are presented who had polymorphous ventricular tachycardia (PMVT) occurring during atrioventricular (AV) block. There were five men and four women with a mean age of 80 +/- 9 years. Five patients had organic heart disease and the remaining four had primary conduction disease (bundle branch block). AV block was complete in four patients (2:1 in three, and paroxysmal in two). The mean ventricular cycle length (of the AV block rhythm) was 1567 +/- 203 ms. The mean QT interval was 0.64 +/- 0.09 s and the mean QTc was 0.51 +/- 0.06 s. When compared to a similar control group with AV block but without PMVT, the ventricular cycle length was similar but the QT and QTc were significantly longer. PMVT was usually of short duration (eight beats to 12 s) and in seven of these nine patients, frequent premature ventricular beats (PVBs) were recorded at various times from the occurrence of PMVT. This is in contrast to the control patients in whom PVBs were detected in one patient only. In conclusion, patients with AV block who develop PMVT usually have longer QT intervals and have detectable PVBs on routine ECGs, unlike similar patients with AV block but without PMVT. In a patient with AV block, a QT interval above 0.60 s and PVBs on the ECG seem to indicate an increased risk for the development of PMVT.

Aged↗
PubMed1985

Echocardiographic evaluation of patients with systemic sarcoidosis.

Echocardiographic evaluation of 42 patients with sarcoidosis disclosed 13 patients (group A) with abnormalities compatible with sarcoid heart involvement such as thickening or thinning of the septum (eight patients), pericardial effusion (four patients), and increased end-diastolic dimension of the left ventricle with decreased systolic function (three patients). The remaining 29 patients (group B) were diagnosed as having normal echocardiograms. The clinical data revealed no statistically significant difference between the groups regarding age, sex, chest x-ray stage, activity, and previous heart disease. Group A patients had older clinical onset of the disease (52 vs 83 months; p less than 0.05) and higher incidence of ECG abnormalities than group B patients. There were no statistically significant differences between the groups regarding two-dimensional echocardiographic internal dimensions of both ventricular chambers. The radionuclear right ventricular ejection fraction was low in both groups and the left ventricular ejection fraction was depressed in group A patients (p less than 0.01). As observed in pathologic studies, the septum is a target structure which can be characterized echocardiographically. Screening suspected sarcoid heart disease involvement is important to characterize patients with a relatively high risk of clinical cardiac abnormalities such as complete atrioventricular block, ventricular arrhythmias, congestive heart failure, and sudden death.

Adolescent↗
PubMed1985

Efficacy of intravenous amiodarone in the management of paroxysmal or new atrial fibrillation with fast ventricular response.

We tested the efficacy of intravenous amiodarone (5 mg/kg) in slowing ventricular response and/or restoring sinus rhythm in 26 patients with paroxysmal or new atrial fibrillation with fast ventricular response. There were 16 men and 10 women with ages ranging from 35 to 84 years, mean 63 years. Intravenous amiodarone initially slowed the ventricular response in all patients from 143 +/- 27 to 96 +/- 10 beats/min (P less than 0.001). Twelve patients (46%) reverted to sinus rhythm within the first 30 min (range 5 to 30 min, mean 14 +/- 9 min). One patient reverted to atrial flutter after 10 min and 40 min later to sinus rhythm. Six patients (23%) converted to sinus rhythm after 2 to 8 hr and in these 6 cases, the initial slowing in ventricular response obtained with amiodarone persisted until conversion. Seven patients (27%) did not convert to sinus rhythm following amiodarone administration and they required further medical therapy to slow the ventricular response and/or to convert to sinus rhythm. No serious side effects from drug administration were noted. Intravenous amiodarone appears as a highly effective medication in the conversion or control of new onset atrial fibrillation with fast ventricular response.

Adult↗
PubMed1985

Right ventricular dysfunction in acute inferoposterior myocardial infarction. An echocardiographic and isotopic study.

We analyzed right ventricular (RV) regional wall motion by two-dimensional echocardiographic (2D echo) and multigated acquisition radionuclear (MUGA) studies in 104 patients with acute inferoposterior myocardial infarction (AIPMI). Sixty-eight patients (65 percent) had 2D echo RV regional wall motion abnormalities (RV dysfunction(RVD) group) while 36 patients showed no 2-D echo RV regional wall motion abnormalities (no-RVD group). The RVD group had a higher incidence of jugular venous engorgement (p less than 0.05), Kusmaul's sign, (p less than 0.05) complete atrio-ventricular block (p less than 0.05), and in-hospital death (p less than 0.02). The RVD group had significantly higher 2-D echo RV end-systolic dimensions (p less than 0.005) and lower values of percentage of fractional shortening (%FS) (p less than 0.005) in the long and short axis of the RV four-chamber view than patients in the no-RVD group and a control group of 20 patients with normal hearts. There was no statistical significant difference in the 2-D echo RV end-diastolic dimensions among the three groups. Patients in the RVD group had a lower MUGA derived RV ejection fraction (EF) than patients in the no-RVD and control groups (26.5 +/- 13.2 vs. 46.3 +/- 7 and vs. 50.6 +/- 4, respectively; p less than 0.05). RVD was diagnosed by both 2-D echo and MUGA in 60 of 104 patients (57.7 percent) with a sensitivity for 2-D echo of 92 percent and 79 percent specificity (when compared to the MUGA study). The predictive value for a positive test was 88 percent and for a negative test 86 percent. The accuracy was 87.5 percent. Recognition of regional wall motion abnormalities by 2-D echo permits a prompt and accurate bedside identification of right ventricular dysfunction (RVD) within the first 72 hours of clinical onset. An enlarged RV 2D echo end-diastolic dimension was not a sensitive parameter for the diagnosis of this pathology, whereas an increased end-systolic RV diameter and decreased RV %FS were better indicators of RV dysfunction in patients with acute inferoposterior wall myocardial infarction.

Aged↗
PubMed1985

A simplified QRS scoring system for the estimation of the severity of acute inferior wall myocardial infarction.

Electrocardiographic assessment of the R/Q wave ratio (lead 2) of patients with a first acute inferior wall myocardial infarction (IWMI) offers important indirect quantitative information regarding the severity and extent of the myocardial damage. Eighty-eight consecutive patients with IWMI were investigated by echocardiography and radionuclear angiography. After measuring the R/Q ratio in lead 2 during the ST-wave stabilized stage of myocardial infarction, patients were separated into three groups--group 1 with an R/Q ratio greater than 2; group 2 with an R/Q ratio between 1 to 2; and group 3 with an R/Q ratio less than 1. Utilizing the information thus gathered from the electrocardiogram (ECG) offers a simple and efficient method for early prognosis which merits further investigation.

Adult↗
PubMed1985

Carotid sinus syndrome: an overlooked cause of syncope.

Carotid sinus syncope was diagnosed during a 2-year period in 21 men and 5 women, aged 51 to 80 years, who had experienced 1 to 30 syncopal episodes during periods of time which varied from 1 day to 6 years. In 19 of these patients there was evidence of organic heart disease. Carotid sinus hypersensitivity of the cardioinhibitory type was present in 14 patients, the vasodepressor type in 1 patient, and a mixed type in 7 patients. In four patients with the cardioinhibitory response, the possibility of the vasodepressor response was not excluded. A pacemaker was placed in 17 patients, deferred in 4 patients and refused by 5 patients. Follow-up of patients with pacemakers over 9.5 +/- 7.0 (SD) months revealed recurrence of symptoms in two patients due to a previously unrecognized vasodepressor response. Follow-up of the patients without pacemakers was brief (4.6 +/- 3.7 months), and they remained asymptomatic, except for one patient with recurring vertigo.

Aged↗
PubMed1985

Echocardiographic findings of mitral and tricuspid valve prolapse in primary pulmonary hypertension.

Echocardiographic findings in six patients with primary pulmonary hypertension are presented. Four of six patients had abnormal septal motion with prolapse of mitral and tricuspid valves. The other two had none of the three echocardiographic abnormalities. It is possible that hemodynamic changes in ventricular pressure gradients across the interventricular septum cause an abnormal septal motion and secondary AV valve prolapse.

Adolescent↗
PubMed1985

High-output cardiac failure as a presenting symptom of plasma cell leukemia.

A patient presented with high-output cardiac failure and was found to have plasma-cell leukemia. No cause for the cardiac failure was found, and there was no response to treatment with diuretics and thiamine. Chemotherapy for the leukemia resulted in resolution of the cardiac failure, suggesting that the latter was caused by the leukemia--a hitherto unreported association.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1984

Left and right ventricular function in inferior acute myocardial infarction and significance of advanced atrioventricular block.

Of 139 consecutive patients with a first inferior acute myocardial infarction, 26 (19%) had advanced atrioventricular (AV) block and 113 (81%) did not. All were evaluated by 2-dimensional echocardiography (2-D echo) and radionuclide angiography. Patients with advanced AV block had lower radionuclide left ventricular (LV) ejection fraction (51 +/- 10 vs 58 +/- 11%, p less than 0.01), higher LV wall motion score on 2-D echo (5.6 +/- 2.6 vs 3.1 +/- 2.7, p less than 0.001), lower radionuclide right ventricular (RV) ejection fraction (32 +/- 15 vs 39 +/- 16%, p less than 0.001) and higher RV wall motion score on 2-D echo (3.4 +/- 1.7 vs 1.5 +/- 2, p less than 0.002) than did patients without AV block. The incidence rate of RV dysfunction was higher in patients with advanced AV block (78 vs 40%, p less than 0.02), and the mortality rate was also higher (although not significantly) in patients with advanced AV block (15 vs 6%). In conclusion, patients with inferior acute myocardial infarction and advanced AV block have larger infarct sizes (as seen on radionuclide angiography and 2-D echo) and lower RV and LV function than patients without AV block. This finding may explain the higher mortality rate observed in this group.

Adult↗