The American journal of cardiology
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Clinical Trial Controlled Clinical Trial
Hemodynamic and neurohumoral effects of levosimendan, a new calcium sensitizer, at rest and during exercise in healthy men.
Levosimendan is a novel inodilator that increases the calcium sensitivity of troponin C in a calcium-dependent way. Cardiac function (impedance cardiography, systolic time intervals), neurohumoral responses at rest and during exercise at 2 workloads, and peripheral blood flow (plethysmography) were studied in 14 healthy young men. Vehicle and 2 doses of levosimendan (6.5 micrograms/kg, low dose [LD]; and 25 micrograms/kg, high dose [HD]) were given intravenously in a crossover study. ⋯ During exercise at the lower workload, HD levosimendan increased cardiac output by 1.5 L/min (p < 0.05), compared with that caused by vehicle, by an increase in heart rate, with the stroke volume being unchanged. Electromechanical systole was shortened significantly (20 ms, p < 0.001 after HD; 12 ms, p < 0.01 after LD). At the higher workload, no effects on electromechanical systole or cardiac output compared with that associated with administration of vehicle were seen, but the mean heart rate increased (p < 0.001, LD and HD) and mean diastolic blood pressure decreased (p < 0.01, HD).(ABSTRACT TRUNCATED AT 250 WORDS)
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This study was performed to establish whether signal-averaged electrocardiography can aid in the diagnosis of the familial form of arrhythmogenic right ventricular cardiomyopathy in order to determine the severity of the disease and to predict ventricular arrhythmias. In arrhythmogenic right ventricular cardiomyopathy there is a fatty fibrous substitution of myocardium, which is the substrate for delayed myocardial activation; this is responsible for the abnormalities seen on the signal-averaged electrocardiogram (SAECG). Seventy-five members of 11 families, both healthy and with various forms of the disease, were studied using a signal-averaged electrocardiographic technique. ⋯ In contrast, 90.6% of patients with an abnormal SAECG had the disease, and only subjects with arrhythmogenic right ventricular cardiomyopathy had ventricular arrhythmias. The abnormality on the SAECG appears to be correlated with the severity of the disease. Signal-averaged electrocardiography does not seem useful in diagnosing the minor forms of the disease and it does not give precise information about electrical instability in these patients.
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Clinical Trial Controlled Clinical Trial
Safety of implantation of a cardioverter-defibrillator without general anesthesia in an electrophysiology laboratory.
Implantable cardioverter-defibrillators (ICDs) have conventionally been implanted in an operating room under general anesthesia. This study was performed to evaluate ICD implantation without general anesthesia by 2 electrophysiologists in an electrophysiology laboratory. Between February and September 1994, 27 consecutive patients (22 men and 5 women, mean age 59 +/- 15 years) who underwent ICD implantation by 2 electrophysiologists were included in this study. ⋯ Mean time from implantation to discharge was 2.5 +/- 2.1 days. During late follow-up (n = 23; mean 12.4 +/- 5.8 weeks), all devices were functioning appropriately. In conclusion, this report demonstrates that ICD implantation can be successfully and safely performed by a team of 2 electrophysiologists using local anesthesia and intravenous sedation.(ABSTRACT TRUNCATED AT 250 WORDS)
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Editorial Comparative Study
Short-term use of intravenous milrinone for heart failure.