Very Low Left Atrial Volume and Mortality in Patients Submitted to Pulmonary CT Angiography: A Clue to the Presence of a Blocked Pulmonary Circulation - The 64th Annual Conference of the Israel Heart Society & The Israel Society of Cardiothoracic Surgery, 25-26 April 2017

Zach Rozenbaum ^1,5 Yoav Granot ¹ Paul Turkeltaub ¹ Tzahi Hadad ² Moshe Iluz ² Hezzi Shmueli ^3,5 Tomer Ziv-Baran ⁴ Shlomo Berliner ^1,5 Galit Aviram ^2,5

¹Internal Medicine, Sourasky Medical Center
²Radiology, Sourasky Medical Center
³Cardiology, Sourasky Medical Center
⁴Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University
⁵Sackler Faculty of Medicine, Tel Aviv University

Introduction:
Low left atrial (LA) volumes have been associated with adverse outcomes in association with various pulmonary pathologies. The four chamber volumetric analysis (4CVA) technology can be used to detect low LA volumes at real time in individuals who undergoing computed tomographic pulmonary angiography (CTPA).

Objectives:
Disclose the association between very small left atria (VSLA) and mortality in patients submitted to CTPA in whom pulmonary emboli were excluded.

Methods:
Following exclusion of patients with pulmonary emboli we evaluated mortality curves in consecutive 241 patients who had both echocardiograms and non-gated CTPA that were performed within 24 hours. The lower 10^th percentile (≤19.2ml according to echo, and ≤26ml according to CTPA) was compared with higher volumes after indexing to body surface area (BSA). Results: LA volume according to CTPA correlated well with the volume according to echocardiogram (correlation coefficient 0.609; p<0.001). Independent predictors of mortality were CTA LA/BSA≤26ml (HR 2.71, 95% CI 1.15-6.37; p=0.022), age (HR 1.029, 95% CI 1.009-1.049; p=0.005), malignancy (HR 4.083, 95% CI 1.504-11.083; p=0.006), and hemoglobin concentrations (HR 0.853, 95% CI 0.751-0.97; p=0.015).

Conclusions:
VSLA, assessed by the 4CVA technology can be indicative of a worse outcome also in patients who undergo CTPA and in whom pulmonary emboli were excluded.