Cardiac Rhythm after the Mustard Operation for Complete Transposition of the Great Arteries

Abstract

The Mustard operation corrects the effects of congenital transposition of the great arteries by creating an intraarterial baffle to direct pulmonary venous blood to the tricuspid orifice and systemic venous blood to the mitral orifice. To identify the long-term effects of this procedure, we followed 372 patients with complete transposition of the great arteries who survived the Mustard operation for at least three months. The mean follow-up period was 4.5 years (range, 0.4 to 15.9); the mean age at operation was 2.0 years. Mean resting heart rates were consistently lower than those for age-matched normal children. Seventy-six per cent of the patients had sinus rhythm during the year of operation--a figure that decreased to 57 per cent by the end of the eighth postoperative year. Twenty-five patients died during the follow-up period, nine suddenly. Life-table analysis revealed a cumulative survival rate of 91 per cent for 11 years and 71 per cent for 15 years after the operation. No strong risk factor for sudden unexpected death identified. This study demonstrates that extended survival among patients with transposition can be expected after the Mustard operation. However, over time there is a decreasing prevalence of normal sinus rhythm in survivors, as well as a small risk of sudden death.

ACC/AHA 2008 Guidelines for the Management of Adults With Congenital Heart Disease

“…Although it may arise after nearly any procedure that involves a right atriotomy (even simple closure of an ASD), the incidence is clearly highest after the Mustard, Senning, and Fontan operations, in which as many as 30% to 50% of patients can be expected to develop a symptomatic episode during extended follow-up. 144, 145 The term "intraatrial reentrant tachycardia" (IART) has become the custom- ary designation for this arrhythmia to distinguish it from classic atrial flutter seen in structurally normal hearts. 146 -148 Whereas typical atrial flutter involves a very predictable circuit around the tricuspid annulus that results in the familiar ECG appearance of sawtooth flutter waves at a rate of 300 beats per minute, IART can involve novel circuits around surgical scars and patches that generate a much wider spectrum of atrial rates and P-wave contours.…”

“…Generally, IART tends to be slower than typical flutter, with atrial rates in the range of 170 to 250 beats per minute. 144 In the setting of a healthy AV node, these rates will frequently allow a pattern of 1:1 AV conduction that may result in hemodynamic instability, syncope, or possibly death. 149 -151 Even if the ventricular response rate is safely titrated, sustained IART of long duration can be responsible for thromboembolic events.…”

“…Direct trauma to the sinoatrial node or its arterial supply occurs fairly frequently after the Mustard, Senning, Glenn, and Fontan operations. 139,144,176,177 The likelihood of a patient developing IART or atrial fibrillation becomes significantly increased in this setting. Furthermore, patients with suboptimal hemodynamics may become symptomatic owing to chronotropic incompetence and the loss of AV synchrony.…”

Pacemaker and Defibrillation Implantation in Patients with Transposition of the Great Arteries

“…Following Senning or Mustard repair, d-TGA patients are at high risk for developing sinus node dysfunction, while l-TGA patients are at a greater risk for developing AV block, particularly following surgical or catheter-based procedures. [12][13][14][15][16][17][18] Initial device implantation occurred at a much earlier age in individuals with d-TGA. It is likely that the earlier need for surgical intervention contributed to this finding.…”

Sudden cardiac death in children.

“…28 Holter analysis indicates that loss of sinus rhythm is frequent in patients who have undergone the Mustard operation.27-29 Postoperative electrophysiological testing reveals atrial flutter to be the most frequently induced arrhythmia.30 Although the correlation is not strong, atrial tachyarrhythmias have been the only predictor of sudden cardiac death in this group. 27 There is evidence that the arterial switch procedure31 for the repair of d-TGA will reduce the incidence of electrophysiological abnormalities. 32 The other large group of patients in the study by Silka et a19 had dilated cardiomyopathy.…”