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J M Wahl

Publications and source records attributed to J M Wahl.

10 recordsLinked to original sources
PubMed1995

Endocarditis-associated paravalvular abscesses. Do clinical parameters predict the presence of abscess?

STUDY OBJECTIVE: To determine whether standard clinical and transthoracic echocardiographic criteria considered to be suggestive of the presence of endocarditis-associated paravalvular abscess are predictive of which patients would benefit from reliable but invasive transesophageal echocardiographic investigations for abscess. DESIGN: Retrospective chart review. SETTING: A 630-bed university hospital. PATIENTS: Forty-eight patients with 51 episodes of definite endocarditis and 24 paravalvular abscesses. MEASUREMENTS AND RESULTS: A comparison of abscess and nonabscess populations revealed that clinical parameters (patient demographics, valvular involvement, presence of a prosthesis, infection with a virulent organism, pericarditis, persistent fever, persistent bacteremia, congestive heart failure, history of intravenous drug use, embolization) and transthoracic echocardiographic parameters were insensitive predictors of the presence of abscess. The only statistically significant correlate was the presence of previously undetected atrioventricular or bundle branch block. Paravalvular abscesses were common in our population and were associated with increased mortality. Improved survival correlated with the absence of mitral valve involvement and the absence of moderate-to-severe congestive heart failure. CONCLUSIONS: Given the accuracy and safety of transesophageal echocardiography and the unreliability of clinical and transthoracic echocardiographic criteria, we recommend that transesophageal echocardiography be considered in all endocarditis patients with previously unrecognized conduction disturbances, aortic or prosthetic valve involvement, or both, or indications for valve replacement, or all of the foregoing.

Abscess↗
PubMed1991

Prognostic significance of valvular regurgitation in patients with infective endocarditis.

PURPOSE: Doppler ultrasound is a sensitive modality for detecting and quantitating valvular regurgitation in patients with infective endocarditis. Because valvular regurgitation leads to heart failure, we evaluated the prognostic significance of Doppler-detected valvular regurgitation in patients with endocarditis who had not yet developed clinical heart failure. PATIENTS AND METHODS: We reviewed the medical records of 65 patients with a clinical diagnosis of infective endocarditis from May 1985 to March 1990. A total of 49 patients were included in the study: 33 patients with native valve endocarditis and 16 patients with prosthetic valve endocarditis. The initial Doppler echocardiogram was examined in these patients to determine the presence and degree of valvular regurgitation. RESULTS: Significant (moderate to severe) valvular regurgitation was detected in 23 (47%) patients. The presence or absence of significant valvular regurgitation did not predict the development of congestive heart failure, the need for surgery, or death (p = NS). The development of congestive heart failure was significantly associated with the need for surgery (p less than 0.0001) and death (p less than 0.05). CONCLUSION: We conclude that the detection of significant valvular regurgitation in patients with infective endocarditis who have not yet developed heart failure is not predictive of future complications nor does the absence of significant valvular regurgitation identify a group of patients with a more favorable prognosis. In our series, patients who developed congestive heart failure had a significantly higher incidence of surgery and death. Therefore, decisions regarding clinical management in patients with infective endocarditis should not be made solely on the presence or absence of echocardiographically detected valvular regurgitation.

Adult↗
PubMed1986

Limitations of premature ventricular complex morphology in the diagnosis of myocardial infarction.

To determine the diagnostic value of Q-waves (greater than or equal to 0.04 seconds duration) in premature ventricular complexes (PVC's) for the presence of myocardial scar, we examined 12-lead electrocardiograms and multiple lead rhythm strips obtained before and after exercise at the time of thallium-201 myocardial imaging in 970 patients. PVC's were found in 233 patients, 112 of whom had fixed thallium-201 perfusion defects indicative of myocardial scar. PVC's occurring during exercise were excluded from the analysis. Twenty-one patients had Q-wave PVC's in one or more electrocardiographic leads. Of those, 14 patients (67%) had myocardial scar in the suggested location. Myocardial scar was more common among patients with Q-wave PVC's than in patients without (67% vs. 36%, p less than 0.01). However, only 6 of 13 patients (46%) with Q-wave PVC's but no diagnostic sinus beats actually had myocardial scar. The remaining seven patients had Q-wave PVC's, no myocardial scar, and no evidence of myocardial ischemia suggested by angina during exercise, exercise electrocardiogram or thallium-201 imaging. We conclude that although Q-wave PVC's indicate the presence of myocardial scar in 67% of patients, they yield little or no additional diagnostic information to that obtained from the sinus beats

Adult↗
PubMed1985

Scintigraphic characterization of Q wave and non-Q-wave acute myocardial infarction.

This study examines the scintigraphic features of patients in Killip class I or II after acute myocardial infarction (AMI) with relation to ECG changes. The 41 consecutively studied patients (23 men and 18 women) with first AMI were divided into two groups: group 1 (n = 25) had Q wave AMI, and group 2 (n = 16) had non-Q wave AMI. Rest thallium-201 myocardial scintigrams and radionuclide ventriculograms were obtained 10 days (mean) after AMI. The thallium images were divided into 15 segments in three projections and assessed qualitatively and quantitatively. Fixed perfusion defects were present in at least one segment in 23 patients (92%) in group 1 and in eight patients (50%) in group 2 (p = 0.007). All but one patient in group 1 (4%) and three patients in group 2 (19%) had perfusion defects (fixed or reversible). The number of segments with perfusion defects was 5.6 +/- 2.6 in group 1 and 2.9 +/- 2.3 in group 2 (p = 0.002); the peak creatine kinase was 1280 +/- 880 Units/L in group 1 and 360 +/- 340 Units/L in group 2 (p less than 0.001); the left ventricular ejection fraction was 38 +/- 14% in group 1 vs 43 +/- 15% in group 2 (p = NS). Thus fixed perfusion defects are present in 92% of patients with Q waves and in 50% of patients with no Q waves.

Aged↗
PubMed1985

Prognostic implications of normal exercise thallium 201 images.

We studied 455 patients (mean age, 51 years) in whom exercise thallium 201 scintigrams performed for suspected coronary artery disease were normal. Of those, 322 (71%) had typical or atypical angina pectoris and 68% achieved 85% or more maximal predicted heart rate. The exercise ECGs were abnormal in 68 patients (15%), normal in 229 (50%), and inconclusive in 158 (35%). Ventricular arrhythmias occurred during exercise in 194 patients (43%). After a mean follow-up period of 14 months, four patients had had cardiac events, sudden cardiac death in one and nonfatal myocardial infarctions in three. None of the four patients had abnormal exercise ECGs. Two had typical and two had atypical angina pectoris. Normal exercise thallium 201 images identify patients at a low risk for future cardiac events (0.8% per year), patients with abnormal exercise ECGs but normal thallium images have good prognoses, and exercise thallium 201 imaging is a better prognostic predictor than treadmill exercise testing alone, because of the high incidence of inconclusive exercise ECGs and the good prognosis in patients with abnormal exercise ECGs.

Adult↗
PubMed1980

New deletion mutant of bacteriophage T5.

Deletion mutants of bacteriphage T5 can be identified by analyzing the DNA content of single plaques, after alkaline denaturation, by agarose gel electrophoresis. Use of this procedure has resulted in the isolation of a new mutant, designated del2, that lacks a 1.6% segment located 68 to 70% from the left end of T5 DNA. This segment occurs between the early and late gene regions of T5 DNA.

DNA, Viral↗