Watchman implantation was associated with the development of severe Group 1 pulmonary hypertension (mean PA 60 mmHg) 6 years post-procedure in a 90-year-old woman.
Case Report (n=1)
Mechanical exclusion of the left atrial appendage may lead to chronic natriuretic peptide deficiency, potentially triggering or exacerbating pulmonary hypertension and right heart failure in older patients.
Abstract Introduction The left atrial appendage (LAA) is an essential endocrine organ responsible for significant secretion of atrial and brain natriuretic peptides (ANP and BNP), which regulate vascular tone, natriuresis, and pulmonary vascular remodelling. Occlusion of the LAA with endovascular devices such as the Watchman prevents blood stasis and clot formation in the LAA and is is a widely accepted alternative to anticoagulation in patients with atrial fibrillation (AF). However, suppression of ANP/BNP release after mechanical LAA exclusion may contribute to impaired pulmonary vasodilation, leading to pulmonary hypertension and subsequent right heart failure. Case A 90-year-old woman with AF s/p Watchman implantation 6 years back (no longer on anticoagulation) and permanent pacemaker placement, who presented with 6 months of with progressive dyspnea, pedal edema, orthopnea despite escalating diuretics. Echocardiography in 2012 had demonstrated normal left ventricular (LV) function and pulmonary artery systolic pressure of ∼25-30 mmHg. A Right-heart catheterisation that was done this year before presentation revealed severe pulmonary hypertension (RA 18 mmHg, PA 104/37 mean 60 mmHg, PVR 8.7 Wood units, LVEDP 21 mmHg) with preserved LV systolic function. Computed tomography showed no parenchymal lung disease or thromboembolic obstruction. A CT Chest angiogram showed dilated pulmonary artery as in the figure. She was treated with sildenafil and ambrisentan for Group I pulmonary arterial hypertension, with limited improvement. Discussion This case illustrates a potential complication of LAA occlusion. A 90 year old female with a Watchman device was diagnosed with Group 1 pulmonary hypertension with normal left heart function. It is hypothesised that the device reduces the atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) in the LAA, leading to diminished natriuretic signalling. This reduction may impair cGMP-mediated pulmonary vasodilation, increase pulmonary vascular resistance through arterial vasoconstriction, and ultimately promote right heart failure. Most existing literature shows an initial increase in BNP after Watchman implantation, which later declines. This BNP could subsequently increase due to heart failure later in the disease like in this case. Diagnosing a 90-year old patient with Group 1 PH is very rare and unique. As the LAA is a source of ANP and BNP, its mechanical exclusion may blunt the cardioprotective effects of these hormones, predisposing older patients with preexisting diastolic dysfunction to pulmonary hypertension and right-sided failure. We propose that chronic natriuretic peptide deficiency following Watchman implantation may trigger or exacerbate PH, particularly in older patients with preexisting diastolic dysfunction. This abstract is funded by: None
Raghavan et al. (Fri,) conducted a case report in Atrial fibrillation and pulmonary hypertension (n=1). Watchman implantation was evaluated on Development of severe pulmonary hypertension. Watchman implantation was associated with the development of severe Group 1 pulmonary hypertension (mean PA 60 mmHg) 6 years post-procedure in a 90-year-old woman.