Myocardial bridging in a survivor of sudden cardiac near-death: role of intracoronary doppler flow measurements and angiography during dobutamine stress in the clinical evaluation.

Abstract

Extensive myocardial bridging in the left anterior descending coronary artery was found in a 46 year old survivor of sudden cardiac near-death. Positron emission tomography and dobutamine stress echocardiography revealed ischaemia in the myocardium distal to the bridging. Spasm was excluded as cause of the ischaemia by intracoronary infusion of acetylcholine. Further evaluation of the haemodynamic importance of the bridging using intracoronary Doppler flow velocity measurements revealed an abnormal flow reserve. Dobutamine stress during coronary angiography caused increased mechanical compression during diastole. This was accompanied by multiple premature ventricular contractions. After a debridging operation the flow velocity reserve was normal. The abnormalities found during dobutamine stress had disappeared. Unexpectedly, a spasm was inducible. This may have been due to local oedema or scar formation after the operation. For the evaluation of the haemodynamic importance of myocardial bridging, intracoronary Doppler flow velocity measurements and angiography during dobutamine stress may be helpful in clinical decision making. (Heart 1997;77:280-282) Keywords: dobutamine stress; coronary flow reserve; myocardial bridging; sudden cardiac death Sudden cardiac death in young and middle aged subjects may be caused by (congenital) abnormalities of the coronary arteries. In this report a case of extreme myocardial bridging was found as the precipitating factor for ventricular arrhythmia in a survivor of sudden cardiac near-death.Case A 46 year old man collapsed during lunch in a factory canteen. Cardiopulmonary resuscitation was started immediately. On the arrival of the ambulance ventricular fibrillation was present. After defibrillation, sinus rhythm and adequate circulation were established. In the hospital the heart rate was 50 beats/min, blood pressure 130/70 mm Hg, and the patient respired spontaneously.

Coexistent Coronary Artery Disease or Myocardial Bridging in Patients with Hypertrophic Cardiomyopathy Using Coronary CT Angiography

“…MB is a well-recognized phenomenon that has a prevalence of 1-3% in the general population (25), though it occurs far more frequently in patients with HCM with variable prevalence rates between 15 and 41% (6,8,15,25). In the present study, the prevalence of coexistent MB was 42.7%, including partial encasement (14.7%) and full encasement (28.0%), in agreement with previous studies.…”

“…Whether MB in HCM is related to poor clinical outcomes has been controversial (25,26). In studies of pediatric patients with HCM, MB has been associated with cardiac disease severity and an increased risk of sudden cardiac death, while no significant correlation was found in adult patients (6,25). In our study, the presence of MB was not associated with specific symptoms in adults with HCM.…”

“…Therefore, early detection of coexistent CAD in HCM is of high importance. HCM than with non-HCM (6). Although most occurrences of MB are thought to be innocent, in some cases, they may cause angina pectoris, MI, life-threatening ventricular arrhythmias, or even sudden cardiac death (6)(7)(8).…”

Attenuation Drop of Intra-Mural Coronary Segment Observed at Diastolic Phase of Coronary CT Angiography Predicts Significant Systolic Compression of Myocardial Bridge

“…Although MB is generally considered a benign anomaly, it may be associated with clinical manifestations that have been linked to dynamic compression [5][6][7][8][9][10][11]. The treatment strategy is guided by the presence of reduced myocardial perfusion, which is closely related to extent of dynamic compression [18,19].…”

Is there a Title Role for Renal Sympathetic Denervation in Patients with Symptomatic Myocardial Bridging Refractory to Clinical Treatment and Ventricular Arrhythmias?

“…The presence of a portion of the vesel under the "bridge" of contractile myocardium repeatedly results in arterial compression during each systole. While frequently asymptomatic, this condition in many cases may be guilty of adverse events including angina, myocardial ischemia [3], acute coronary syndromes [4][5][6], left ventricular dysfunction and stunning [7], arrhythmias [8,9], and even sudden cardiac death [10,11]. Described rates of myocardial bridging vary based on the mode of evaluation.…”