Clinical cardiology
-
Noncardiac chest pain is a common costly phenomenon in the cardiology setting. Recent research suggests that panic disorder, a highly distressful yet treatable anxiety disorder, occurs in a significant proportion of noncardiac chest pain patients. This article reviews research on the prevalence of panic disorder in patients seen in cardiology settings for unexplained chest pain. ⋯ Panic disorder and the potential consequences of its nonrecognition by physicians are examined. Current psychological and pharmacologic treatments are reviewed. Recommendations on the management of panic patients in the cardiology setting are provided.
-
The term torsade de pointes refers to polymorphic ventricular tachycardia that occurs in the setting of an abnormally long QT interval. While the most common cause is treatment with QT prolonging drugs, torsade de pointes also occurs in the congenital long QT syndromes and in the setting of acquired heart block or severe electrolyte disturbance, notably hypokalemia. ⋯ Treatment consists of recognition of the syndrome, correction of underlying electrolyte abnormalities, and withdrawal of any offending drugs. Magnesium, isoproterenol, or cardiac pacing provides specific antiarrhythmic therapy in torsade de pointes.
-
Clinical cardiology · Feb 1997
ReviewThe vital role of papillary muscles in mitral and ventricular function: echocardiographic insights.
The two left ventricular (LV) papillary muscles are small structures but are vital to mitral valve competence. Partial or complete rupture, complicating acute myocardial infarction, causes severe or even catastrophic mitral regurgitation, potentially correctable by surgery. Papillary muscle dysfunction is a controversial topic in that the role of the papillary muscle itself, in causing mitral regurgitation post infarction, has been seriously questioned; it is less confusing if this syndrome is attributed not only to papillary muscle but also to adjacent LV wall ischemia or infarction. ⋯ Papillary muscle hypertrophy accompanies LV hypertrophy of varied etiology and may have a significant role in producing dynamic late-systolic intra-LV obstruction in hypertrophic cardiomyopathy and other hyperdynamic hypertrophied LV chambers. All the above abnormalities can be adequately assessed by 2-D echocardiography and the Doppler modalities. In selected cases, transesophageal echocardiography can provide additional valuable data by improving visualization of papillary muscles and mitral apparatus.
-
Clinical cardiology · Jan 1997
Transesophageal pulsed Doppler echocardiographic evaluation of left atrial systolic performance in hypertrophic cardiomyopathy: combined analysis of transmitral and pulmonary venous flow velocities.
Hypertrophic cardiomyopathy (HC) is characterized by impaired left ventricular (LV) diastolic function due to an increase in LV wall thickness. The severity of this disease varies depending on the localization and extent of the hypertrophied myocardium and the presence and extent of myocardial disarray or fibrosis. ⋯ Peak velocity and duration of TMF and PVF during atrial systole by transesophageal pulsed Doppler echocardiography are useful indices of hemodynamic abnormalities between the left atrium and the left ventricle during atrial systole, particularly a forceful atrial contraction mismatched to the left atrial afterload and severity of LV diastolic dysfunction, in HC.
-
Clinical cardiology · Jan 1997
Abnormal signal-averaged electrocardiograms in patients with incomplete right bundle-branch block.
A hypothesis was formulated that regional delayed activation of the right ventricle, as seen in incomplete right bundle-branch (IRBBB) aberrancy, may simulate late potential activity and may be responsible for abnormal signal-averaged electrocardiograms (SAECGs). No previous studies have specifically addressed this issue in this particular group of patients (with IRBBB). Therefore, the aim of the present study was to investigate the incidence of abnormal SAECGs in patients with IRBBB. If this were confirmed, our purpose would further be to investigate ways of reducing the false positive results. ⋯ Delayed terminal conduction observed in IRBBB may cause a high incidence of false positive late potentials on SAECGs. Based on this study, we propose that this can be largely remedied if the optimal criteria for the presence of late potentials in patients with IRBBB always include the combination of QRSD and either RMS or LAS.