Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Michael J. Zema is active.

Publication


Featured researches published by Michael J. Zema.


The American Journal of Medicine | 1983

Detection of left ventricular dysfunction in ambulatory subjects with the bedside Valsalva maneuver

Michael J. Zema; Michele Caccavano; Paul Kligfield

The bedside sphygmomanometric determination of the arterial pressure response during the Valsalva maneuver was incorporated into the routine physical examination of ambulatory subjects. Four distinct Valsalva responses were noted: ultrasinusoidal, sinusoidal, absent overshoot, and square wave. The absent overshoot response was further divided into positional and constant types--the latter consistently exhibiting this response regardless of body position. Correlation with resting left ventricular ejection fraction was obtained by radionuclide cineangiography in 200 patients, of whom 81 had left ventricular systolic dysfunction (ejection fraction less than 0.50). Significant differences in the mean left ventricular ejection fraction were found in subjects with an ultrasinusoidal response (0.65 +/- 0.11), sinusoidal response (0.55 +/- 0.15), constant absent overshoot response (0.37 +/- 0.18), and square wave response (0.16 +/- 0.04) to Valsalva maneuver. The sensitivity of an abnormal Valsalva response (absent overshoot or square wave responses) for the bedside detection of left ventricular systolic dysfunction was 69 percent, and the predictive value of an ultrasinusoidal Valsalva response for normal ejection fraction was 93 percent. It is concluded that the high predictive accuracy of the Valsalva maneuver makes this simple bedside technique a valuable method for assessing resting left ventricular function.


American Journal of Cardiology | 2003

Effectiveness and tolerability of a new lipid-altering agent, gemcabene, in patients with low levels of high-density lipoprotein cholesterol.

Harold E. Bays; James M. McKenney; Carlos A. Dujovne; Helmut G. Schrott; Michael J. Zema; Jack Nyberg; Diane E MacDougall

This study evaluated the efficacy and tolerability of gemcabene, a new lipid-altering agent, in a double-blind, randomized, dose-response study of 161 patients with high-density lipoprotein (HDL) cholesterol of <35 mg/dl and serum triglyceride (TG) levels of either >/=200 (n = 94) or <200 mg/dl (n = 67). After a 6-week, placebo, dietary lead-in period, patients were administered either 150, 300, 600, or 900 mg of gemcabene or placebo once daily for 12 weeks. In the TG >/=200 mg/dl stratum, gemcabene significantly increased serum HDL cholesterol by 18% with corresponding significant increases of 6% in both apolipoprotein A-I and A-II levels at the 150-mg dose. HDL cholesterol levels also increased 12% at the 300-mg dose; however, this did not reach statistical significance. Also, in the TG >/=200 mg/dl stratum, serum TG levels were significantly reduced by 27% and 39% at the 150- and 300-mg doses of gemcabene, respectively. No significant differences were found in serum HDL cholesterol or TG levels in the TG >/=200 mg/dl groups that received 600 or 900 mg of gemcabene, or in TG <200 mg/dl groups administered any dose of gemcabene. However, at these higher 600- and 900-mg doses, gemcabene significantly reduced serum low-density lipoprotein (LDL) cholesterol levels by 15% to 25%, respectively, in both TG strata, with proportionate decreases in the levels of apolipoprotein B. Gemcabene was well tolerated with a frequency of adverse events similar to that of placebo. In conclusion, at the lower doses, gemcabene significantly increased HDL cholesterol and reduced TG serum levels in patients with low HDL cholesterol and TG >/=200 mg/dl. At the higher doses, gemcabene significantly reduced LDL cholesterol levels in all patients with low HDL cholesterol.


Journal of Electrocardiology | 1990

Electrocardiographic tall R waves in the right precordial leads

Michael J. Zema

Electrocardiographic tall R waves in the right precordial leads may be present in patients with posterior myocardial infarction, right ventricular hypertrophy, various conduction disturbances, and some forms of cardiomyopathy and in clinically otherwise normal subjects with prominent anterior electromotive forces. Clinical uncertainty most often arises in distinguishing possible prior posterolateral myocardial infarction (PMI) from the unusual normal variant (PAF). The ECGs and VCGs of 15 subjects with posterolateral infarction were compared with tracings from 12 subjects with no evidence of cardiac disease, all individuals demonstrating tall R waves (R/S greater than 1.0 in V1 and/or V2) in the right precordial leads on surface ECG. By standard ECG, the infarction group was characterized by taller T waves in leads V1 and V2, shorter T waves in V6, greater T2-T6 index, and a more negative two variable function as described by Nestico. By VCG, the infarction group was characterized by a more anteriorly oriented T loop, more leftward maximal frontal plane QRS vector and a lower calculated -45 degrees/ab, as described by Suzuki. An algorithm was proposed that permitted proper classification (PAF vs. PMI) based on ECG criteria in 75% of subjects with 90% accuracy. This compared favorably with performance of the Frank vectorcardiogram, including using more recently proposed criteria. Routine use of the VCG, therefore, in this clinical setting may no longer be justified.


Angiology | 1985

Prognosis After Myocardial Infarction- Prediction in Ambulatory Patients by Use of the Bedside Valsalva Maneuver

Michael J. Zema

One hundred survivors of first myocardial infarction were studied prior to hospital discharge by 24 hour ambulatory electrocardiography as well as radio nuclide ventriculography. The bedside Valsalva maneuver, with simple sphyg momanometric determination of arterial pressure response, was performed 6 weeks post infarction and patients were followed for a mean of 22 months. The arterial pressure response pattern provided a semiquantitative estimate of rest ing left ventricular systolic function when related to the radionuclide ejection fraction (SIN, 0.56±0.13; ABO, 0.43±0.18; SQW, 0.16±0.06) (P < 0.02). Ab normal Valsalva responses (ABO and SQW) were found more commonly in patients with diminished left ventricular systolic function and high grade ven tricular arrhythmias. The SQW response pattern was highly predictive of fu ture sudden cardiac death. The bedside Valsalva maneuver, performed 2-4 weeks after hospital discharge, upon the ambulatory patient is a simple, safe, inexpensive and uniformly applicable method which may serve as the basis for a strategy with which to approach the post-infarction patient regarding risk stratification and further clinical management.


Angiology | 1983

Serum Drug Concentrations in Patients with Ischemic Heart Disease After Administration of a Sustained Release Procainamide Preparation

Michael J. Zema; Timothy Mirando

Despite widespread marketing of a sustained release preparation of pro cainamide hydrochloride (PROCAN-SR, Parke-Davis), published literature demonstrating its efficacy in maintaining uniform serum drug levels over a 6-hour dosing interval is derived from only normal healthy volunteers. Thirty-three patients with ischemic heart disease, ages 30-88 years, were administered 1-4g/24 hours (mean dose 34 mg/kg/day) of PROCAN-SR in 4 equally divided doses on a Q6H schedule. After achievement of steady-state equilibrium drug concentration, procainamide and N-acetylprocainamide levels were determined by high-performance liquid chromatography on sera obtained from blood samples drawn 2, 3.5 and 5 hours after an oral dose. Mean maximal procainamide and N-acetylprocainamide serum concentra tions were 4.6± 1.8 ug/ml and 4.2±2.1 ug/ml respectively. Mean minimal concentrations were 3.5± 1.7 ug/ml and 3.6±2.0 ug/ml respectively. The mean change in drug concentration was small (1.1 ug/ml procainamide and 0.6 ug/ml N-acetylprocainamide) with procainamide and N-acetylprocainamide con centrations varying only by 27 and 15 percent respectively. These data demonstrate in a population of patients with ischemic heart disease, that Q6H dosing with a sustained release procainamide hydrochloride preparation (PROCAN-SR, Parke-Davis) is associated with only a small ac ceptable variation between maximal and minimal serum procainamide and N-acetylprocainamide concentrations. This preparation should, therefore, offer greater patient convenience and compliance without sacrificing antiar rhythmic efficacy.


Journal of Clinical Ultrasound | 1982

Feasibility of detailed M‐mode echocardiographic examination in markedly obese adults: Prospective study of 50 patients

Michael J. Zema; Michele Caccavano


Chest | 1990

Heart failure and the bedside Valsalva maneuver.

Michael J. Zema


American Journal of Cardiology | 1980

Left anterior fascicular block and inferior myocardial infarction

Michael J. Zema


American Journal of Cardiology | 2010

Poor R Wave Progression Revisited

Michael J. Zema


American Journal of Cardiology | 1992

The bedside Valsalva maneuver in the diagnosis of congestive heart failure

Michael J. Zema

Collaboration


Dive into the Michael J. Zema's collaboration.

Top Co-Authors

Avatar

Michele Caccavano

Memorial Hospital of South Bend

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

James M. McKenney

Virginia Commonwealth University

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge