Clinical cardiology
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Clinical cardiology · Dec 2001
Case ReportsRight ventricular electrocardiographic leads for detection of Brugada syndrome in sudden unexplained death syndrome survivors and their relatives.
Sudden unexplained death syndrome (SUDS) is a sudden death syndrome in previously healthy Southeast Asian young adults without any structural causes of death. Many SUDS survivors show electrocardiographic (ECG) evidence of RSR' and ST elevation in leads V1 to V3, which is similar to the ECG pattern in Brugada syndrome. However, in many cases transient normalization of the ECG does not make diagnosis with standard 12-lead ECG possible. ⋯ Our data suggest that these new right ventricular leads ECG may be helpful in detecting Brugada syndrome in SUDS survivors and their relatives.
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Clinical cardiology · Oct 2001
A critique of the new ST-segment criteria for the diagnosis of acute myocardial infarction in patients with left bundle-branch block.
Recently, electrocardiogram (ECG) criteria have been proposed for the diagnosis of acute myocardial infarction (AMI) in the presence of left bundle-branch block (LBBB). However, clinical experience indicates that such ECG changes indicative of AMI are occasionally noted in clinically stable patients with LBBB, raising concerns about the specificity of the proposed criteria. ⋯ Thus, recently proposed ST-segment criteria for the diagnosis of AMI in patients with LBBB are appropriate. However, stable > or = 5 mm +STs are occasionally found in leads with predominantly negative QRS complexes, particularly of large amplitude (mean value 46.0, range [28.0-71.0] mm) in the absence of AMI. In such patients presenting with symptoms suggestive of AMI, further non-ECG confirmation of probable underlying AMI should be sought.
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Clinical cardiology · Sep 2001
Comparative StudyC-Reactive protein as a risk factor for left ventricular thrombus in patients with acute myocardial infarction.
Elevated C-reactive protein (CRP) has been found to correlate with higher risk for cardiac events in patients with acute myocardial infarction (AMI). It has been suggested that CRP may be involved in initiation process of coagulation; however, the role of CRP level in the formation of left ventricular (LV) thrombus has not been studied. ⋯ These results suggest that CRP is a risk factor for LV thrombus in patients with AMI.
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Clinical cardiology · Aug 2001
ReviewSpinal cord stimulation for chronic intractable angina pectoris: a unified theory on its mechanism.
The use of spinal cord stimulation (SCS) for chronic intractable anginal pain was first described in 1987. Numerous studies have demonstrated its efficacy in improving exercise tolerance, decreasing frequency of anginal episodes, and prolonging time to electrocardiographic signs of ischemia. This review will examine the potential mechanisms of this antianginal effect and propose a unified hypothesis explaining it. ⋯ Improvement of myocardial blood flow at the microvascular level has been demonstrated by positron emission tomography (PET). A decreased sympathetic tone has been shown by norepinephrine kinetics, tests of sympathetic reflexes, and the use of ganglionic blockers. We hypothesize that SCS exerts its beneficial effects by decreasing pain and decreasing sympathetic tone, the result of which is decreased myocardial oxygen consumption along with an improved myocardial microcirculatory blood flow.
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Clinical cardiology · Jul 2001
Multicenter Study Comparative StudyA double-blind, multicentered study comparing the accuracy of diagnostic markers to predict short- and long-term clinical events and their utility in patients presenting with chest pain.
Millions of patients present annually with chest pain, but only 10% have myocardial infarction (MI). We recently reported comparative sensitivity and specificity of available markers in the diagnosis of MI; however, optimum interpretation of marker results requires prognostic follow-up data. ⋯ With the possible exception of myoglobin, each of the diagnostic markers displayed similar prognostic performance in patients with chest pain presenting to emergency departments. The most appropriate markers to triage patients with chest pain, which has both adequate early diagnostic sensitivity and prognostic accuracy, are the CK-MB subforms.