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N H Kander

Publications and source records attributed to N H Kander.

6 recordsLinked to original sources

A randomized pilot trial of brief versus prolonged heparin after successful reperfusion in acute myocardial infarction.

Controversy exists as to whether and how long heparin treatment is necessary after infarct vessel recanalization. To determine the role of heparin, patients with suitable angiographic features after reperfusion therapy were randomly allocated to receive a brief infusion of intravenous heparin for less than or equal to 24 hours (group 1), adjusted to a partial thromboplastin time of 2 times control or a prolonged infusion for greater than or equal to 72 hours (group 2), using the same titration mechanism. Patients were excluded for complex intimal dissections, large residual filling defects, less than Thrombolysis in Myocardial Infarction grade 3 flow pattern or greater than 50% residual stenosis. Heparin was sustained except for discontinuation 2 to 4 hours before periaccess sheath removal, or if significant bleeding (greater than or equal to 2 units blood transfusion) occurred. The primary endpoints were 1-week patency determined by repeat catheterization or recurrent ischemia, or both, and the incidence of bleeding complications. Fifty patients were randomized, 25 in both groups. Baseline variables were similar; 14 group 1 and 15 group 2 patients received thrombolytic treatment; 20 patients in each group had coronary angioplasty. Two documented reocclusions occurred in both groups. Significant bleeding complications occurred in 0 of 25 (0%) group 1 versus 6 of 25 (24%) group 2 patients (p less than 0.05). Thus, in low-risk patients after successful reperfusion, prolonged heparin therapy does not protect against rethrombosis and is associated with a significantly higher rate of bleeding complications. Therefore, prolonged heparin therapy for greater than 24 hours does not appear to be justified in low-risk patients with successful reperfusion.

Drug Administration Schedule↗

Long-term follow-up of patients treated with coronary angioplasty for acute myocardial infarction.

Long-term follow-up data for patients treated with coronary angioplasty (PTCA) for acute myocardial infarction are limited. Therefore the long-term outcome of 336 consecutive patients treated with PTCA at a median of 4.5 hours (range 0.5 to 48 hours) from symptom onset was evaluated. The in-hospital mortality was 11.1% (37 patients). Follow-up is complete for 293 of 299 (98%) hospital survivors at a median of 24 months. Of patients discharged, the mean age was 55 +/- 11 years, 49% received intravenous thrombolytic therapy, 53% had multivessel coronary artery disease, and the mean ejection fraction was 48 +/- 10%. Post-discharge survival was 96.1% at 1 year and 93.6% at 2 years by life table analysis. Post-discharge survival was independently predicted by no prior myocardial infarction (96.9% versus 87.3% 2-year survival, p less than 0.001 by log rank analysis) and infarct artery patency at hospital discharge (which had its major impact on survival early after hospital discharge: [97.4% versus 93.4% 1-year survival but 94.2% versus 93.4% 2-year survival; overall p = 0.02]). For patients with analyzable ventriculograms at hospital discharge, ejection fraction greater than or equal to 40% was also a significant independent predictor of survival (98.1% versus 85.8% 2-year survival, p = 0.01). For patients with a successful PTCA, time from symptom onset to catheterization and angioplasty less than or equal to 4 hours versus greater than 4 hours was also an independent predictor of outcome (97.1% versus 91.4% 2-year survival; p = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗

Coronary revascularization after intravenous tissue plasminogen activator for unstable angina pectoris: results of a randomized, double-blind, placebo-controlled trial.

To determine the role of intravenous tissue plasminogen activator (t-PA) in unstable angina, it was compared with placebo in a randomized, double-blind trial. Forty patients with angina at rest and provocable ischemia (pacing induced) had baseline coronary angiography, study drug infusion and then repeat angiography at 20 +/- 9 hours. All patients received diltiazem, nitrates, beta blockers, aspirin and intravenous heparin. During study drug infusion (150 mg over 8 hours), refractory ischemia necessitating emergency bypass surgery (CABG) or coronary angioplasty (PTCA) occurred in 4 of 20 t-PA patients compared with 1 of 20 placebo patients (p = 0.21). Before discharge, revascularization for persistent, provocable ischemia and a residual stenosis greater than or equal to 60% was as follows: t-PA patients, 8 PTCA and 7 CABG; placebo patients, 11 PTCA and 8 CABG (p = 0.39). Quantitative angiographic percent diameter stenosis of the culprit artery at baseline and follow-up was: t-PA 71 +/- 17 and 63 +/- 22; placebo 70 +/- 19 and 67 +/- 22 (difference not significant). However, 3 t-PA patients compared with no placebo patients demonstrated an insignificant (less than 60% diameter) residual stenosis and averted PTCA (p = 0.14). There were no complications of PTCA in the 8 t-PA patients; in contrast, 3 of 11 placebo patients had abrupt closure, necessitating emergency CABG in 2 (p = 0.23). Thus, intravenous t-PA in unstable angina can eliminate the need for PTCA in a few patients, does not appear to decrease the overall or emergency rate of revascularization procedures and may facilitate the safety of PTCA.

Angina Pectoris↗

A randomized controlled trial of hospital discharge three days after myocardial infarction in the era of reperfusion.

To evaluate the feasibility and cost savings of hospital discharge three days after acute myocardial infarction, we screened 507 consecutive patients prospectively for clinical complications and exercise-test performance. Of 179 patients whose condition was classified as uncomplicated (no angina, heart failure, or arrhythmia 72 hours after admission), 126 underwent early exercise testing and 90 had no provocable myocardial ischemia. Eighty of these patients were randomly assigned to early (day 3) or conventional (days 7 to 10) hospital discharge. Seventy-six of them had received coronary reperfusion therapy (thrombolysis, angioplasty, or both). At six months of follow-up, there were no deaths or new ventricular aneurysms, and the early-discharge and conventional-discharge groups had similar numbers of hospital readmissions (6 and 10), reinfarctions (none and 5), and patients with angina (3 and 8). In the early-discharge group, 25 of 29 previously employed patients returned to work 40.7 +/- 21.9 days (mean +/- SD) after admission, as compared with 25 of 27 patients in the conventional-discharge group, who returned to work after a mean of 56.9 +/- 30.3 days (P = 0.054). The mean cumulative hospital and professional charges were $12,546 +/- 3,034 in the early-discharge group, as compared with $17,868 +/- 3,688 in the conventional-discharge group (P less than 0.0001). In carefully selected patients with uncomplicated myocardial infarction, hospital discharge after three days is feasible and leads to a substantial reduction in hospital charges. Before this strategy can be widely recommended, however, its safety must be confirmed in larger prospective clinical trials.

Clinical Trials as Topic↗

An analysis of the safety of performing dobutamine stress echocardiography in an ambulatory setting.

Dobutamine echocardiography has become widely used in the past decade in the evaluation of patients with suspected coronary artery disease who are unable to undergo exercise treadmill or bicycle testing. The safety of this procedure has been studied in a hospital-based setting. However, no studies thus far have evaluated the safety of this procedure in an office-based setting, remote from a hospital. We performed dobutamine echocardiography on 127 patients in an office-based setting, remote from a hospital. Throughout the course of this study there were no deaths, myocardial infarctions, sustained episodes of ventricular tachycardia, or syncopal episodes associated with dobutamine infusion. The frequency of noncardiac side effects was 29%, the majority of which were nausea, vomiting, and paresthesias. Three patients had nonsustained ventricular tachycardia, none of whom had symptoms. We conclude that dobutamine echocardiography is safe, well tolerated, and useful in an office-based setting.

Adult↗