Coronary artery disease
Long-Term Cardiovascular Outcomes in Patients With Angina Pectoris Presenting With Bundle Branch Block

https://doi.org/10.1016/j.amjcard.2011.01.039Get rights and content

Long-term outcomes of unselected patients with angina pectoris and bundle branch block (BBB) on initial electrocardiogram are not well established. The Olmsted County Chest Pain Study is a community-based cohort of 2,271 consecutive patients presenting to 3 Olmsted County emergency departments with angina from 1985 through 1992. Patients were followed for major adverse cardiovascular events (MACEs) including death, myocardial infarction, stroke, and revascularization at 30 days and over a median follow-up period of 7.3 years and for mortality only through a median of 16.6 years. Cox models were used to estimate associations between BBB and cardiovascular outcomes. Mean age of the cohort on presentation was 63 years, and 58% were men. MACEs at 30 days occurred in 11% with right BBB (RBBB), 8.8% with left BBB (LBBB), and 6.4% in patients without BBB (p = 0.17). Over a median follow-up of 7.3 years, patients with BBB were at higher risk for MACEs (RBBB, hazard ratio [HR] 1.85, 95% confidence interval [CI] 1.44 to 2.38, p <0.001; LBBB, HR 2.04, 95% CI 1.62 to 2.56, p <0.001) compared to those without BBB. Over a median of 16.6 years, the 2 BBB groups had lower survival rates than patients without BBB (RBBB, HR 2.19, 95% CI 1.73 to 2.78, p <0.001; LBBB, HR 3.32, 95% CI 2.67 to 4.13, p ≤0.001), but after adjustment for multiple risk factors an increased risk of mortality for LBBB remained significant. In conclusion, appearance of LBBB or RBBB in patients presenting with angina predicts adverse long-term cardiovascular outcomes compared to patients without BBB.

Section snippets

Methods

Complete medical records of eligible patients were obtained through resources of the Rochester Epidemiology Project (REP), which allows comprehensive capture of details of health care experiences including outpatient care of all residents of Olmsted County, Minnesota (OC).9 The OC Health Care Utilization and Expenditures Database, which is linked to the REP, contains detailed line-item information on health services use and expenditures incurred by every member of the population for as long as

Results

During the study period, 6,801 residents of OC presented to an emergency department with a first episode of acute chest pain. Of these 2,271 (33.4%) met the criteria for angina and were followed as study subjects for a median of 7.3 years for MACEs. Of ineligible patients cardiac disease accounted for 6.7% of presenting syndromes including ST-segment elevation myocardial infarction in 5.5%, stable angina pectoris in 1.0%, and aortic dissection in 0.2%. Noncardiac causes of chest pain accounted

Discussion

Our study is the longest and most comprehensive observation of a population-based cohort of consecutive patients with angina who displayed RBBB or LBBB on initial electrocardiogram. During follow-up, which extended into the current era, the pattern of RBBB on presenting electrocardiogram predicted poor cardiovascular outcomes over 7 years and greater mortality rate of 15 years compared to those without BBB, but these differences were largely attributable to a greater burden of associated risk

Acknowledgment

We acknowledge Jonathan L. Halperin, MD, for his masterful editorial comments.

References (26)

Cited by (0)

This study was made possible by the Rochester Epidemiology Project, Rochester, Minnesota (Grant R01-AR30582 from the National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, Maryland).

Drs. Bansilal and Aneja contributed equally to this article.

View full text