Comprehensive evaluation of intermittent mechanical valve obstruction: a retrieval study of 16 cases
Authors: Kalkan S , Guner AHMET , Gursoy OZAN , Kalcik MACIT , Ozkan MEHMET 
Published: February 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The intermittent stuck valve is a rarely defined clinical situation, which can be life-threatening or benign, and the clinical features are not well-known.

Purpose
A thorough investigation of the intermittent mechanical stuck valve"s etiology, diagnostic and treatment methods, and identifying parameters are associated with clinical severity

Methods
Over 11 years (2010- 2021), 16 patients were subsequently selected from referrals to the Kosuyolu Training and Research Hospital"s echocardiography department. We collected the data retrospectively.

Results
The evaluated patients consisted of 12 bi-leaflet mitral valve replacements (MVR) and two mono-leaflet MVR. Etiologies were classified as follows; residual chord with four patients, obstructive thrombus (OT) with two patients, non-obstructive thrombus (NOT) with two patients, vegetation with two patients, pannus, and OT coexistence with one patient, solely pannus with one patient. One of the residual chord patients with the frequency one of three-beat severe intermittent mitral regurgitation (MR) presented in dyspnea and underwent redo MVR. The other residual chord patients were in the mild condition who had lesser entrapment frequency. One of the two patients with OT had an ischemic cerebrovascular accident (CVA) with intermittent severe mitral stenosis (MS), while the other was in severe dyspnea. These two patients also underwent redo-MVR. Intermittent stuck valve due to NOT (n:2) presented with dyspnea. Both patients presented with intermittent moderate MR. Two patients presented with endocarditis with severe intermittent MR. One patient had obstruction one of the three beats due to the pannus formation who underwent surgery. One patient who recovered with TT had pannus and NOT coincidentally with a stuck valve in one of the three beats.
One of the patients with mono-leaflet MVR had pannus and OT. In the other patient with mono-leaflet MVR, a stuck valve was observed in one of 12 beats secondary to arrhythmia.
In the collected data, there were two aortic valve replacements (AVR). One patient had moderate aortic regurgitation due to prominent calcification; the other had moderate obstruction due to pannus. We decided on follow-up medical treatment for these patients with the aortic valve. In the patient with pannus, stuck valve formation occurred one of six beats, and moderate aortic regurgitation arose one of two beats in the patient with calcification.

Conclusions
The intermittent stuck valve is rarely defined, may have catastrophic outcomes and necessitates a comprehensive approach. It requires elaborative examination in symptomatic patients with prosthetic valves. When making a treatment decision in these patients, as in other native or prosthetic valve patients, the degree of regurgitation or stenosis is essential. In particular, for intermittent stuck valves, the frequency of entrapment should play a fundamental role in making treatment decisions Abstract table 1 Abstract table 2