Published online Dec 26, 2021. doi: 10.4330/wjc.v13.i12.733
Peer-review started: March 30, 2021
First decision: June 17, 2021
Revised: July 1, 2021
Accepted: November 24, 2021
Article in press: November 24, 2021
Published online: December 26, 2021
Processing time: 272 Days and 14.4 Hours
Left atrial (LA) enlargement is a marker of increased risk in the general population undergoing stress echocardiography. African American (AA) patients with hypertension are known to have less atrial remodeling than whites with hypertension. The prognostic impact of LA enlargement in AA with hypertension undergoing stress echocardiography is uncertain.
To investigate the prognostic value of LA size in hypertensive AA patients undergoing stress echocardiography.
This retrospective outcomes study enrolled 583 consecutive hypertensive AA patients who underwent stress echocardiography over a 2.5-year period. Clinical characteristics including cardiovascular risk factors, stress and echocardiographic data were collected from the electronic health record of a large community hospital. Treadmill exercise and Dobutamine protocols were conducted based on standard practices. Patients were followed for all-cause mortality. The optimal cutoff value of antero-posterior LA diameter for mortality was assessed by receiver operating characteristic analysis. Cox regression was used to determine variables associated with outcome.
The mean age was 57 ± 12 years. LA dilatation was present in 9% (54) of patients (LA anteroposterior ≥ 2.4 cm/m2). There were 85 deaths (15%) during 4.5 ± 1.7 years of follow-up. LA diameter indexed for body surface area had an area under the curve of 0.72 ± 0.03 (optimal cut-point of 2.05 cm/m2). Variables independently associated with mortality included age [P = 0.004, hazard ratio (HR) 1.34 (1.10-1.64)], tobacco use [P = 0.001, HR 2.59 (1.51-4.44)], left ventricular hypertrophy [P = 0.001 , HR 2.14 (1.35-3.39)], Dobutamine stress [P = 0.003, HR 2.12 (1.29-3.47)], heart failure history [P = 0.031, HR 1.76 (1.05-2.94)], LA diameter ≥ 2.05 cm/m2 [P = 0.027, HR 1.73 (1.06-2.82)], and an abnormal stress echocardiogram [P = 0.033, HR 1.67 (1.04-2.68)]. LA diameter as a continuous variable was also independently associated with mortality but LA size ≥ 2.40 cm/m2 was not.
LA enlargement is infrequent in hypertensive AA patients when traditional reference values are used. LA enlargement is independently associated with mortality when a lower than “normal” threshold (≥ 2.05 cm/m2) is used.
Core Tip: In hypertensive African American patients referred for stress testing, left atrial (LA) enlargement was infrequent when using the established references values for the general population. Indexed LA Antero-posterior diameter has a superior area under the curve compared to LA diameter alone for discrimination of survivors and non-survivors. LA enlargement is an independent predictor of mortality on long-term follow-up when assessed as a continuous variable or when using a lower reference value derived from our population.