Role of Left Ventricular Dysfunction in Systemic Sclerosis-Related Pulmonary Hypertension.

BACKGROUND: In systemic sclerosis (SSc), pulmonary hypertension remains a significant cause of morbidity and mortality. Although conventionally classified as group 1 pulmonary arterial hypertension, systemic sclerosis-related pulmonary hypertension (SSc-PH) is a heterogeneous disease. The contribution of left-sided cardiac disease in SSc-PH remains poorly understood. RESEARCH QUESTION: How often does left ventricular (LV) dysfunction occur in SSc among patients undergoing right heart catheterization and how does coexistent LV dysfunction with SSc-PH affect all-cause mortality in this patient population? STUDY DESIGN AND METHODS: We conducted a retrospective, observational study of 165 patients with SSc who underwent both echocardiography and right heart catheterization. LV dysfunction was identified using LV global longitudinal strain (GLS) on speckle-tracking echocardiography based on a defined threshold of > -18%. SSc-PH was defined by a mean pulmonary artery pressure > 20 mmHg. RESULTS: Among patients with SSc who have undergone right heart catheterization, LV dysfunction occurred in 74.2% with SSc-PH and 51.2% without SSc-PH. The median survival of patients with SSc-PH and LV dysfunction was 67.9 (95% CI, 38.3-102.0) months, with a hazard ratio of 12.64 (95% CI, 1.73-92.60) for all-cause mortality when adjusted for age, sex, SSc disease duration, and FVC compared with patients with SSc without pulmonary hypertension with normal LV function. INTERPRETATION: LV dysfunction is common in SSc-PH. Patients with SSc-PH and LV dysfunction by LV GLS have increased all-cause mortality. This suggests that LV GLS may be helpful in identifying underlying LV dysfunction and in risk assessment of patients with SSc-PH.

Light Chain Testing Abnormalities Among Patients With Transthyretin Amyloid Cardiomyopathy Referred for Technetium-99m Pyrophosphate Imaging.

Clinical algorithms stipulate that transthyretin amyloid cardiomyopathy (ATTR-CM) can be diagnosed noninvasively by technetium-99m pyrophosphate (PYP) imaging when light chain (AL) amyloidosis has been excluded. We sought to define the distribution of light chain abnormalities and final diagnosis of ATTR-CM among patients referred for PYP imaging. We conducted a retrospective cohort study of 378 sequential patients with suspected ATTR-CM, referred for PYP imaging from October 2014 to January 2019. PYP scans were adjudicated as per guidelines. We found that 97 patients (26%) had abnormal plasma cell dyscrasia (PCD) markers, including serum free light chain (FLC) and/or urine/serum immunofixation electrophoresis (IFE). After exclusions for incomplete data or known AL amyloidosis, the final study population with abnormal PCD testing was n = 82. Final adjudication of amyloidosis was determined by multidisciplinary clinical assessment and/or tissue biopsy. The median age of cohort was 75 (68 to 81) years, 88% were men, and 33% were Black. Of the 82 patients, 62 had positive PYP scans (76%) and 20 had negative PYP scans (24%). A total of 64 patients had adjudicated ATTR-CM, confirmed by tissue biopsy in 41 (64%). Of those with confirmed ATTR-CM, 44 (69%) had abnormal FLC ratio between 1.65 and 3.1 and normal IFE. In conclusion, among patients referred for technetium-99m-PYP imaging for suspected ATTR-CM, 26% exhibited abnormalities of PCD markers. An FLC ratio 1.65 to 3.1, with normal IFE was noted in 69% of those with ATTR-CM, suggesting that ATTR-CM can be diagnosed noninvasively without cardiac biopsy in patients with positive PYP scan and similar plasma cell testing results.