Indexed Left Atrial Volume by Echocardiography as an Indicator of Left Heart Disease in Patients with Scleroderma and Suspected Pulmonary Hypertension

Jean Deschamps Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Benjamin Fox Division of Respiratory Medicine, Asaf Harofeh Hospital, Tzrifin, Israel Lawrence Rudski Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Robert Schlesinger Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Ali Abualsaud Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Igal Sebag Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Jonathan Afilalo Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Marie-Josee Blais Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Mark Eisenberg Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Dominique Joyal Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Fay Blenkhorn Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Lyda Lesenko Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada Michele Giovinazzo Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada David Langleben Azrieli Heart Center, Department of Medicine, Jewish General Hospital, McGill University, Canada, Quebec, Canada

Background: Scleroderma (SCL) is an important cause of pulmonary arterial hypertension (PAH), but there is high prevalence of left ventricular diastolic dysfunction (LVDD) and post-capillary pulmonary hypertension (PH). We previously demonstrated a high incidence of occult left heart disease (LHD) in patients with SCL and PH using catheterization-derived Left Ventricular End Diastolic Pressure measurements and optional saline challenge. Indexed left atrial volume (LAVi) is a validated measurement supporting a diagnosis of LHD and LVDD. It has previously been studied in PH from LHD, but not other forms of PH or SCL. We hypothesized that LAVi can predict pre- vs. post-capillary PH etiology.

Methods: We retrospectively studied 131 patients from 2010 to 2017, reviewing the index right/left catheterization (RHC/LHC) with saline challenge, and complete transthoracic echocardiogram (TTE) performed within 3 months. TTEs were re-analyzed for LAVi and LHD indices, RV function and Pulmonary Pressures by a blinded echocardiographer. LHD was determined by RHC/LHC measure of PAWP or LVEDP > 15 mm interpreted by a blinded physician.

Results: There were 30 subjects with no PH, 57 with PAH, and 44 with LHD by RHC/LHC. ROC analysis yielded an AUC of 0.578 for LAVi to discriminate between pre-capillary and post-capillary PH. A LAVi >= 33 mL/m2 yielded a sensitivity of 0.29 and specificity of 0.89 to rule-in LHD.

Conclusion: Measurement of LAVi by TTE can assist in detecting LHD in SCL and/or PH. Many centers rely on RHC alone, without saline challenge. In a diuresed patient with PH and a low wedge pressure, LHD may thus be missed. LAVi > 33 mL/m2 should suggest LHD even when hemodynamics suggest otherwise. LAVi may be used as an exclusionary adjunct to RHC/LHC to confirm a PAH diagnosis. LAVi may prove useful in screening patients with PH to avoid catheterization.

Lawrence Rudski

Jewish General Hospital