Survival of patients with left bundle-branch block after out-of-hospital cardiac arrest

Abstract

Complete left bundle-branch block (LBBB) is an adverse prognostic sign of mortality and morbidity, especially when associated with underlying heart disease.1Baldasseroni S. Opasich C. Gorini M. et al.Italian Network on Congestive Heart Failure Investigators. Left bundle-branch block is associated with increased 1-year sudden and total mortality rate in 5517 outpatients with congestive heart failure: a report from the Italian network on congestive heart failure.Am Heart J. 2002; 143: 398-405Abstract Full Text Full Text PDF PubMed Scopus (662) Google Scholar, 2Eriksson P. Wilhelmsen L. Rosengren A. Bundle-branch block in middle-aged men: risk of complications and death over 28 years. The Primary Prevention Study in Goteborg, Sweden.Eur Heart J. 2005; 26: 2300-2306Crossref PubMed Scopus (138) Google Scholar, 3Fahy G.J. Pinski S.L. Miller D.P. et al.Natural history of isolated bundle branch block.Am J Cardiol. 1996; 77: 1185-1190Abstract Full Text PDF PubMed Scopus (234) Google Scholar, 4Newby K.H. Pisano E. Krucoff M.W. Green C. Natale A. Incidence and clinical relevance of the occurrence of bundle-branch block in patients treated with thrombolytic therapy.Circulation. 1996; 94: 2424-2428Crossref PubMed Scopus (112) Google Scholar To the best of our knowledge, the prognosis of LBBB still remains unclear in patients receiving cardiopulmonary resuscitation for out-of-hospital cardiac arrest (OHCA).The purpose of this report is to describe the short-term (hospital period) as well as long-term (1-year) survival in patients admitted after OHCA in whom the LBBB morphology is seen on the electrocardiogram (ECG).There were 718 victims of OHCA from the East Bohemia region, an area which covers 11,244 km2, who were enrolled prospectively in our follow-up study from April 4, 2002 to August 31, 2004, from whom 560 patients had undergone “out-of-hospital” resuscitation for cardiac arrest due to cardiac aetiology. 149 cases were admitted to hospital.5Pleskot M. Babu A. Kajzr J. et al.Characteristics and short-term survival of individuals with out-of-hospital cardiac arrests in the East Bohemian region.Resuscitation. 2006; 68: 209-220Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar However, standard LBBB criteria were detected on admission ECG in 24 patients.4Newby K.H. Pisano E. Krucoff M.W. Green C. Natale A. Incidence and clinical relevance of the occurrence of bundle-branch block in patients treated with thrombolytic therapy.Circulation. 1996; 94: 2424-2428Crossref PubMed Scopus (112) Google Scholar The basic characteristics of all patients with LBBB are listed in Table 1.Table 1Clinical, pre-hospital and hospital characteristics of hospitalised individuals with left bundle-branch block (n = 24)Age (years) Median69 Range38–79 Mean65.9 ± 10.7>70 years, no. (%)10 (41.7)Male, no. (%)17 (70.8)Risk factor, no. (%) Hypertension (diastolic pressure > 90 mmHg)15 (62.5) Diabetes mellitus7 (29.2) Hypercholesterolemia (cholesterol > 5.7 mmol per liter)6 (25) Smoking7 (29.2)Previous CAD, no. (%)17 (70.8)Initial cardiac rhythm, no. (%) Ventricular fibrillation17 (70.8) Asystole5 (20.8) Pulseless electrical activity1 (4.2) Atrioventricular block1 (4.2)Location, no. (%) Home11 (45.8) Public place13 (54.2)Glasgow coma scale at admission, no. (%) 3–524 (100)Cardiogenic shock, no. (%)15 (62.5)Postanoxic encephalopathy, no. (%)9 (37.5)Artificial pulmonary ventilation, no. (%)23 (95.8)Left ventricular ejection fraction ≤ 35% (ECHO), no. (%)9 (37.5)Revascularisation, no. (%) PCI -Total4 (16.7) -Direct1 (4.2) CABG1 (4.2)ICD, no. (%)5 (20.8)Discharged from acute hospitalization, no. CPC 1 (good cerebral performance)5 CPC 2 (moderate cerebral disability)1 CPC 3 (severe cerebral disability)1CAD: coronary artery disease; ECHO: echocardiography; PCI: percutaneous coronary intervention; CABG: coronary artery bypass graft; ICD: implantable cardioverter-defibrillator; CPC: cerebral performance category (Glasgow–Pittsburgh Categorization of Brain Injury; source: Ref. 6). Open table in a new tab Of those with LBBB, 17 individuals (70.8%) died during hospitalisation (6 died within 48 h after admission). Autopsy diagnoses in hospitalised patients were established in six cases: acute myocardial infarction (three cases), dilated cardiomyopathy (one case), severe coronary artery disease without acute myocardial infarction (two cases). The discharge diagnoses based on examinations including coronary angiography in 7 short-term survivors (29.2%) were as follows: coronary artery disease without acute myocardial infarction (5 cases) and dilated cardiomyopathy (2 cases). A scheme of coronary angiography and its timing is summarised in Figure 1.The analysis of neurological outcomes on discharge from hospital in accordance with Glasgow–Pittsburgh Outcome Categorization (CPC) showed that five out of the seven patients were discharged in good condition (CPC 1) (Table 1).6Brain Resuscitation Clinical Trial I Study GroupA randomized clinical study of cardiopulmonary–cerebral resuscitation: design, methods, and patient characteristics.Am J Emerg Med. 1986; 4: 72-86Abstract Full Text PDF PubMed Scopus (204) Google ScholarDuring the 1-year follow-up, of seven discharged patients, five patients survived without further clinical deterioration and two patients suddenly died (discharged with CPC 2, CPC 3). Importantly, one of the dead patients had an implantable cardioverter-defibrillator. No autopsy in these two cases was performed (Figure 1, Table 1).In conclusion, we found that 16.1% of patients hospitalised for OHCA of cardiac aetiology presented LBBB features on the ECG. The short-term survival in OHCA patients with LBBB was 29.2% and the long-term survival in these patients was 20.8%. Immediate coronary angiography was done only in 12.5% of patients with LBBB, although LBBB may reflect acute myocardial infarction. Complete left bundle-branch block (LBBB) is an adverse prognostic sign of mortality and morbidity, especially when associated with underlying heart disease.1Baldasseroni S. Opasich C. Gorini M. et al.Italian Network on Congestive Heart Failure Investigators. Left bundle-branch block is associated with increased 1-year sudden and total mortality rate in 5517 outpatients with congestive heart failure: a report from the Italian network on congestive heart failure.Am Heart J. 2002; 143: 398-405Abstract Full Text Full Text PDF PubMed Scopus (662) Google Scholar, 2Eriksson P. Wilhelmsen L. Rosengren A. Bundle-branch block in middle-aged men: risk of complications and death over 28 years. The Primary Prevention Study in Goteborg, Sweden.Eur Heart J. 2005; 26: 2300-2306Crossref PubMed Scopus (138) Google Scholar, 3Fahy G.J. Pinski S.L. Miller D.P. et al.Natural history of isolated bundle branch block.Am J Cardiol. 1996; 77: 1185-1190Abstract Full Text PDF PubMed Scopus (234) Google Scholar, 4Newby K.H. Pisano E. Krucoff M.W. Green C. Natale A. Incidence and clinical relevance of the occurrence of bundle-branch block in patients treated with thrombolytic therapy.Circulation. 1996; 94: 2424-2428Crossref PubMed Scopus (112) Google Scholar To the best of our knowledge, the prognosis of LBBB still remains unclear in patients receiving cardiopulmonary resuscitation for out-of-hospital cardiac arrest (OHCA). The purpose of this report is to describe the short-term (hospital period) as well as long-term (1-year) survival in patients admitted after OHCA in whom the LBBB morphology is seen on the electrocardiogram (ECG). There were 718 victims of OHCA from the East Bohemia region, an area which covers 11,244 km2, who were enrolled prospectively in our follow-up study from April 4, 2002 to August 31, 2004, from whom 560 patients had undergone “out-of-hospital” resuscitation for cardiac arrest due to cardiac aetiology. 149 cases were admitted to hospital.5Pleskot M. Babu A. Kajzr J. et al.Characteristics and short-term survival of individuals with out-of-hospital cardiac arrests in the East Bohemian region.Resuscitation. 2006; 68: 209-220Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar However, standard LBBB criteria were detected on admission ECG in 24 patients.4Newby K.H. Pisano E. Krucoff M.W. Green C. Natale A. Incidence and clinical relevance of the occurrence of bundle-branch block in patients treated with thrombolytic therapy.Circulation. 1996; 94: 2424-2428Crossref PubMed Scopus (112) Google Scholar The basic characteristics of all patients with LBBB are listed in Table 1. CAD: coronary artery disease; ECHO: echocardiography; PCI: percutaneous coronary intervention; CABG: coronary artery bypass graft; ICD: implantable cardioverter-defibrillator; CPC: cerebral performance category (Glasgow–Pittsburgh Categorization of Brain Injury; source: Ref. 6). Of those with LBBB, 17 individuals (70.8%) died during hospitalisation (6 died within 48 h after admission). Autopsy diagnoses in hospitalised patients were established in six cases: acute myocardial infarction (three cases), dilated cardiomyopathy (one case), severe coronary artery disease without acute myocardial infarction (two cases). The discharge diagnoses based on examinations including coronary angiography in 7 short-term survivors (29.2%) were as follows: coronary artery disease without acute myocardial infarction (5 cases) and dilated cardiomyopathy (2 cases). A scheme of coronary angiography and its timing is summarised in Figure 1. The analysis of neurological outcomes on discharge from hospital in accordance with Glasgow–Pittsburgh Outcome Categorization (CPC) showed that five out of the seven patients were discharged in good condition (CPC 1) (Table 1).6Brain Resuscitation Clinical Trial I Study GroupA randomized clinical study of cardiopulmonary–cerebral resuscitation: design, methods, and patient characteristics.Am J Emerg Med. 1986; 4: 72-86Abstract Full Text PDF PubMed Scopus (204) Google Scholar During the 1-year follow-up, of seven discharged patients, five patients survived without further clinical deterioration and two patients suddenly died (discharged with CPC 2, CPC 3). Importantly, one of the dead patients had an implantable cardioverter-defibrillator. No autopsy in these two cases was performed (Figure 1, Table 1). In conclusion, we found that 16.1% of patients hospitalised for OHCA of cardiac aetiology presented LBBB features on the ECG. The short-term survival in OHCA patients with LBBB was 29.2% and the long-term survival in these patients was 20.8%. Immediate coronary angiography was done only in 12.5% of patients with LBBB, although LBBB may reflect acute myocardial infarction.