Noemi Bertel1, Fabienne Witassek1, Milo Puhan2, Paul Erne3, Hans Rickli4, Barbara Naegeli5, Giovanni Pedrazzini6, Jean-Christophe Stauffer7, Dragana Radovanovic8. 1. University of Zurich, AMIS Plus Data Center, Epidemiology, Biostatistics and Prevention Institute, 8001 Zurich, Switzerland. 2. University of Zurich, Epidemiology, Biostatistics and Prevention Institute, 8001 Zurich, Switzerland. 3. University of Zurich, AMIS Plus Data Center, Epidemiology, Biostatistics and Prevention Institute, 8001 Zurich, Switzerland; University of Basel, Department of Biomedicine, 4031 Basel, Switzerland. 4. Department of Cardiology, Kantonsspital St. Gallen, 9007 St. Gallen, Switzerland. 5. Department of Cardiology, HerzGefässZentrum Zürich, 8038 Zurich, Switzerland. 6. Department of Cardiology, Cardiocentro Ticino, 6900 Lugano, Switzerland. 7. Department of Cardiology, Hôpital cantonal HFR, 1708 Fribourg, Switzerland. 8. University of Zurich, AMIS Plus Data Center, Epidemiology, Biostatistics and Prevention Institute, 8001 Zurich, Switzerland. Electronic address: dragana.radovanovic@uzh.ch.
Abstract
BACKGROUND: Diagnosis of acute myocardial infarction (MI) is challenging in pacemaker patients. Little is known about this patient group. METHODS: Patients with MI enrolled in the Swiss national AMIS Plus registry between January 2005 and December 2015 were analyzed. All patients with either paced ventricular rhythm or sinus rhythm with intrinsic ventricular conduction (IVC) were included in this study. Outcomes using crude data and propensity score matching were compared between patients with pacemaker rhythm and patients with IVC. The primary endpoint was in-hospital death. RESULTS: Data from 300 patients with paced rhythm and 27,595 with IVC were analyzed. Patients with pacemaker rhythm were older (78.2y vs 65.4y; p<0.001), had more comorbidities (Charlson Index (CCI)>1: 54.0% vs 21.1%; p<0.001) and a higher rate of heart failure upon presentation (Killip class>2, 11.0% vs 5.9%; p<0.001) compared to patients with IVC. Door to balloon time in patients undergoing acute PCI is markedly delayed in contrast to patients with IVC (280min vs 85min; p<0.001). Consequently, crude mortality in patients with pacemakers was high (11.3% vs 4.6%; p<0.001). However, when analyzed with propensity matching for gender, age, CCI>1 and Killip>2, mortality was similar (11.2% vs 10.5%; p=0.70). CONCLUSION: Pacemaker patients with acute MI represent a high-risk group with doubled crude mortality compared to patients without pacemakers, due to higher age and higher Killip class. Diagnosis is difficult and results in delayed treatment. Treatment algorithms for MI with paced rhythm should possibly be adapted to those used for STEMI or new left bundle branch block. CLINICAL TRIALS REGISTRATION: NCT01305785.
BACKGROUND: Diagnosis of acute myocardial infarction (MI) is challenging in pacemaker patients. Little is known about this patient group. METHODS:Patients with MI enrolled in the Swiss national AMIS Plus registry between January 2005 and December 2015 were analyzed. All patients with either paced ventricular rhythm or sinus rhythm with intrinsic ventricular conduction (IVC) were included in this study. Outcomes using crude data and propensity score matching were compared between patients with pacemaker rhythm and patients with IVC. The primary endpoint was in-hospital death. RESULTS: Data from 300 patients with paced rhythm and 27,595 with IVC were analyzed. Patients with pacemaker rhythm were older (78.2y vs 65.4y; p<0.001), had more comorbidities (Charlson Index (CCI)>1: 54.0% vs 21.1%; p<0.001) and a higher rate of heart failure upon presentation (Killip class>2, 11.0% vs 5.9%; p<0.001) compared to patients with IVC. Door to balloon time in patients undergoing acute PCI is markedly delayed in contrast to patients with IVC (280min vs 85min; p<0.001). Consequently, crude mortality in patients with pacemakers was high (11.3% vs 4.6%; p<0.001). However, when analyzed with propensity matching for gender, age, CCI>1 and Killip>2, mortality was similar (11.2% vs 10.5%; p=0.70). CONCLUSION: Pacemaker patients with acute MI represent a high-risk group with doubled crude mortality compared to patients without pacemakers, due to higher age and higher Killip class. Diagnosis is difficult and results in delayed treatment. Treatment algorithms for MI with paced rhythm should possibly be adapted to those used for STEMI or new left bundle branch block. CLINICAL TRIALS REGISTRATION: NCT01305785.