American heart journal
-
American heart journal · Sep 1995
Comparative StudyBaroreflex sensitivity, but not heart rate variability, is reduced in patients with life-threatening ventricular arrhythmias long after myocardial infarction.
Low values of heart rate variability (HRV, a marker of vagal tone) and baroreflex sensitivity (BRS, a marker of vagal reflexes) identify patients at higher risk soon after myocardial infarction (MI). However, it is still unknown whether HRV and BRS correlate with malignant arrhythmias after the recovery from the transient post-MI autonomic disturbance. This study assessed whether HRV and BRS would differ in patients with malignant ventricular arrhythmias occurring long after MI compared with those in a control population. ⋯ However, patients in the VT/VF group had a significantly lower baroreflex sensitivity compared with patients in the control group (4.2 +/- 0.5 vs 8.0 +/- 1.1 msec/mm Hg, p = 0.008). Thus BRS but not HRV was reduced in patients with life-threatening ventricular arrhythmias occurring long after MI. A persistent depression of vagal reflexes may play a role in the occurrence of malignant arrhythmias, and analysis of BRS may potentially be helpful in the identification of patients at high risk long after myocardial infarction.
-
American heart journal · Sep 1995
Review Case ReportsExtrapericardial cardiac tamponade after blunt chest trauma.
-
American heart journal · Aug 1995
Comparative Study Clinical Trial Controlled Clinical TrialGuidance of anticoagulation after intracoronary implantation of Palmaz-Schatz stents by monitoring prothrombin and prothrombin fragment 1 + 2.
The primary objective of this study was to apply a sophisticated coagulation monitoring system including estimation of the concentration of prothrombin fragment 1 + 2 (PTF 1 + 2) and the activity of prothrombin (coagulation factor II or FII) to cases of stent implantation and to compare the results with those of standard coagulation tests. The secondary objective was to detect the incidence after stenting of subacute thrombosis (SAT) and bleeding complications in these patients and to compare the results with those of a group of patients with stent implantation in whom coagulation was monitored exclusively by standard tests. SAT several days after coronary stenting occurs in up to 20% despite aggressive intravenous and overlapping oral anticoagulation. ⋯ The sensitivity, specificity, and accuracy of the PTF1 + 2 test were 100%, 88%, and 88%, respectively. In the control group the incidence of SAT was 17%, with 16.1% for elective versus 18% for nonelective stenting. Major bleeding complications occurred in 10% (study group) and in 11.3% (control group) of patients (no statistical difference).(ABSTRACT TRUNCATED AT 400 WORDS)
-
American heart journal · Aug 1995
Hypotension during dobutamine stress echocardiography: is it related to dynamic intraventricular obstruction?
Although it has been shown that a hypotensive response during dobutamine stress echocardiography is not a marker of coronary artery disease, the mechanism of this response remains unclear. We hypothesize that hypotension during dobutamine stress echocardiography is not related to the development of dynamic intraventricular obstruction. The development of left ventricular outflow obstruction was defined as a late-peaking Doppler velocity profile that exceeded baseline outflow velocity by at least 1 m/sec in 104 consecutive patients undergoing dobutamine stress echocardiography. ⋯ An ischemic response to dobutamine infusion as manifested by the development of new or worsening wall motion abnormalities was seen in 40% of group 1 patients and 34% of group 2 patients (p = 0.77). These data demonstrate that a hypotensive response is not related to the development of dynamic intraventricular obstruction during dobutamine stress echocardiography. Rather, there is a significant association between a higher baseline systolic blood pressure and a hypotensive response during dobutamine infusion.