Case of systolic anterior motion of mitral valve after mitral valve repair

A 56-year-old woman was underwent mitral valve repair for prolapse of the posterior mitral leaflet. Intraoperative transesophageal echocardiography (TEE) showed systolic anterior motion (SAM) of the mitral valve at the weaning from cardiopulmonary bypass (CPB). Sliding technique was easily performed at the second pump run. Intraoperative TEE demonstrated no SAM or residual mitral regurgitation after the second pump run.     

Cibenzoline attenuates systolic anterior motion of the mitral valve after mitral valvoplasty

We report a patient in whom severe hemodynamic instability occurring after mitral valvoplasty (MVP) was successfully treated with cibenzoline. Left ventricular outflow tract obstruction (LVOTO) with mitral regurgitation (MR) resulting from the systolic anterior motion (SAM) of the mitral valve that occurs after MVP often leads to hemodynamic collapse. Patients who develop SAM after MVP have been managed with intravenous volume loading, reduction/discontinuation of inotropic drugs, and with increased afterload, but these strategies were often ineffective. Cibenzoline decreased myocardial contraction, attenuated SAM, and improved hemodynamics in our patient. We recommend that cibenzoline be administered before further surgical manipulation is considered for patients who develop SAM after MVP.     

Modern management of systolic anterior motion of the mitral valve

Systolic anterior motion (SAM) of the mitral valve (MV) can be a life-threatening condition. The SAM can result in severe left ventricular outflow tract obstruction and/or mitral regurgitation and is associated with an up to 20% risk of sudden death (which is substantially lower in hypertrophic cardiomyopathy (HCM)). The mechanisms of SAM are complex and depend on the functional status of the ventricle. The SAM can occur in the normal population, but is typically observed in patients with HCM or following MV repair. Echocardiography (2D, 3D and stress) has a central diagnostic role as the application of echocardiographic SAM predictors allows the incorporation of prevention techniques during surgery and post-operative SAM assessment. Cardiac magnetic resonance imaging has a special role in understanding the dynamic nature of SAM, especially in anatomically atypical hearts (including HCM). This article describes what the clinician needs to know about SAM ranging from pathophysiological mechanisms and imaging modalities to conservative (medical) and surgical approaches and their respective outcomes. A stepwise approach is advocated consisting of medical therapy, followed by aggressive volume loading and beta-adrenoceptor blockade. Surgery is the final option. The correct choice of surgical technique requires an understanding of the anatomical substrate of SAM.     

A short-acting beta-blocker,landiolol, attenuates systolic anterior motion of the mitral valve after mitral valve annuloplasty

Here, we describe three patients with severe hemodynamic instability after mitral valve annuloplasty (MVP) who were treated successfully using a new ultra-short-acting beta-blocker, landiolol hydrochloride. When systolic anterior motion (SAM) of the mitral valve occurs after MVP, left ventricular outflow tract obstruction (LVOTO) and mitral regurgitation (MR) often lead to hemodynamic collapse. Treatment of SAM is very difficult, and transfusion, or the reduction/discontinuation of catecholamine or vasopressor administration, is often ineffective. In our three patients, landiolol hydrochloride decreased the heart rate, markedly attenuated SAM, and improved the hemodynamics. We recommend that landiolol be administered before further surgical manipulation is considered in patients with SAM after MVP.     

Importance of anesthetic management for the patients with systolic anterior motion after mitral valve plasty

Systolic anterior motion (SAM) after mitral valve plasty (MVP) occurs at an incidence of 1 to 4%. The management is related to this condition. Three patients developed SAM just after MVP. In the first patient, a 51-year-old man, volume loading and methoxamine were employed, which elevated arterial pressure, but led to a severer catastrophe. This suggested the indication of mitral valve replacement to the surgeons. The second patient, a 75-year-old woman, underwent re-annuloplasty after the first MVP because of incomplete correction. Before the separation from the second CPB, continuous dopamine infusion was started because we feared that the long CPB time would have impaired LV function. The TEE showed the catastrophe, but it disappeared just after the discontinuation of the dopamine infusion and the administration of propranolol and norepinephrine. The last patient was a 72-year-old woman. For the catastrophe, propranolol was given and an immediate improvement followed with TEE showing no evidence of the catastrophe. The goal for anesthetic management of the catastrophe after MVP is to decrease the hyperdynamic ventricular contraction. We managed SAM by volume loading and discontinuation of beta-stimulants and/or administration of beta-blockers.     

Severe mitral systolic anterior motion complicating aortic valve replacement

This case illustrates a severe dynamic left ventricular outflow obstruction after aortic valve replacement (AVR). This phenomenon is little recognised but probably occurs more frequently than appreciated, and should be considered when managing patients with severe haemodynamic instability after AVR. The possible mechanisms and treatment are discussed.     

Management of intraoperative systolic anterior motion of the mitral valve after valve plasty: a case report

We report a case of intraoperative systolic anterior motion (SAM) of the mitral valve after mitral valve plasty (MVP). A 53-year-old man underwent MVP for mitral regurgitation (MR). MVP was carried out uneventfully. We weaned the patient from cardiopulmonary bypass (CPB) with continuous administration of catecholamines and a vasodilator. However, after the weaning from CPB, transesophageal echocardiography (TEE) detected moderate MR with left ventricular outflow tract obstruction (LVOTO) due to SAM. LVOTO and SAM gradually disappeared after the reduction of catecholamines and volume loading. He was transferred to the intensive care unit postoperatively and extubated 18 hours after operation. Transthoracic echocardiography after operation revealed disappearance of MR. He was discharged from the hospital on postoperative day 15 without complications. We successfully managed MR with LVOTO due to SAM by reduction of catecholamines and volume loading.     

Management of systolic anterior motion of the mitral valve: a mechanism-based approach

Although the mechanism of systolic anterior motion (SAM) of the mitral valve is unknown, it is known to have a multifactorial pathophysiology. Echocardiographic analysis of the mitral leaflet revealed the step-wise progression of SAM, and intraventricular flow analysis revealed the contribution of drag force generated by the misled flow below the posterior leaflet. Although several diverse clinical features of SAM are already known, some key features need to be abstracted from among them to understand the regulation of SAM establishment. This paper reviews past articles that have investigated the mechanism of SAM and proposes a mechanism-based concept to provide insights for better comprehension of SAM recognition.     

Systolic anterior motion of the mitral valve despite the sliding leaflet technique for repair of the mitral valve

We report a systolic anterior motion of the anterior mitral leaflet despite employing the sliding leaflet technique for repair of mitral valve regurgitation. A 65-year-old man with chronic, symptomatic mitral regurgitation due to ruptured chordae tendineae underwent mitral valve repair by quadrangular resection of the posterior leaflet and sliding leaflet technique with ring annuloplasty. After weaning from cardiopulmonary bypass, left ventricular outflow obstruction developed and transesophageal echocardiography demonstrated systolic anterior motion of the mitral valve and severe mitral regurgitation. Non-operative treatment resolved the outflow tract obstruction, systolic anterior motion and mitral regurgitation. We conclude that post-repair systolic anterior motion can still occur after the sliding plasty procedure and that medical treatment can successfully resolve systolic anterior motion and outflow tract obstruction in most patients.