Thirty-year electrocardiographic follow-up after repair of tetralogy of Fallot or atrial septal defect

QRS Complex Enlargement as a Predictor of Ventricular Arrhythmias in Patients Affected by Surgically Treated Tetralogy of Fallot: A Comprehensive Literature Review and Historical Overview

Tetralogy of Fallot (TOF) is a congenital heart disease frequently treated by surgical repair to relieve symptoms and improve survival. However, despite the performing of an optimal surgical repair, TOF patients are at times characterized by a poor long-term survival rate, likely due to cardiac causes such as ventricular arrhythmias, with subsequent sudden death. In the 80s it was irrefutably demonstrated that QRS prolongation ≥180 msec at basal electrocardiogram is a strong predictor for refining risk stratification for ventricular tachycardia in these patients. The aim of this research was to undertake a review of all studies conducted to assess the impact of QRS duration on the development of life-threatening ventricular arrhythmias in repaired TOF subjects.

Long-term electrocardiographic follow-up after repair of tetralogy of Fallot

BACKGROUND

Fallot patients with conduction disturbances are prone to sudden cardiac death. However, knowledge about long-term electrocardiographic changes after Fallot repair is limited.

METHODS

Measurements were performed on electrocardiograms recorded preoperatively, postoperatively, and during annual follow-up in 35 Fallot patients included in three groups: G1 if they received no patch (n = 7), G2 if they received a transannular patch (n = 13), and G3 if they received a pulmonary homograft (n = 15).

RESULTS

PR interval increased over the study period in all groups (Z-score: from 0.9 ± 1.1 to 1.3 ± 0.9 in G1, 0.9 ± 1.2 to 1.7 ± 1.6 in G2, and 0.7 ± 0.7 to 1.4 ± 1.3 in G3). The QRS duration increased during the follow-up at a rate of 1.78 msec/year in G1, 2.34 msec/year in G2 despite pulmonary valve replacement in 10 patients, and 1.81 msec/year in G3 despite conduit replacement in 9. At the later follow-up, the QRS duration was significantly increased (Z= 4.5 ± 3.6 in G1, 5.7 ± 1.4 in G2, and 4.6 ± 1.9 in G3). One patient in each group had QRS duration of 170 msec or longer and the one in G3 had a history of serious ventricular arrhythmia. Three patients had a QTc duration above 460 msec.

CONCLUSIONS

Progressive conduction disorders are noted during long-term follow-up in Fallot patients who received transannular patch but also in those who received no patch or a pulmonary homograft. It suggests that volume overloading related to the transannular patch but also pressure overloading and myocardial injury related to surgery contribute to their development.

Late Atrio-ventricular Block After Arterial Switch for D-transposition of the Great Vessels With Intact Interventricular Septum

Arterial switch operation for transposition of the great arteries without ventricular septal defect usually does not lead to atrio-ventricular conduction disturbances. We discuss the case of a young boy presenting with first and second degree supra hisian atrio-ventricular block late after switch operation.

Mid-term results following surgical treatment of congenital cardiac malformations in adults

The long term consequences of untreated of residual or recurrent lesions pose unique challenges in the growing population of adults with congenitally malformed hearts. In our unit, 335 patients aged from 18 to 72 years, with a mean age of 35 plus or minus 14 years, presented for correction of congenital cardiac disease from September, 1997, through December, 2006. Of the group, 42 (12.5%) had undergone one or more prior surgical procedures, 3 were admitted as emergencies, and a further 10 (3%) had suffered prior cardiac related complications. Symptoms had been noted by 181 patients (54%), and 42 (12.5%) had an established arrhythmia. Chromosomal anomalies were identified in 13 (3.8%), and diagnostic catheterisation was required in 201 (60%) patients. Of the overall group, 2 patients died early (0.6%). Complications occurred in 61 patients (18%), including atrial fibrillation, pneumothorax, postoperative haemorrhage, pericardial or pleural effusions requiring drainage, stroke, complete heart block, endocarditis, wound dehiscence, and peripheral neuropathy. The median length of stay in the intensive care unit and hospital were 2 and 7 days, respectively. Death occurred later in 2 further patients (0.6%), due to atrial fibrillation and pulmonary hypertension. At mean follow-up of 63 plus or minus 30 months, the majority of the remaining patients are well with resolution or significant improvement in their symptoms. Despite the long term deleterious effects of untreated, residual or recurrent congenital cardiac lesions in adults, therefore, we conclude that surgical correction can be achieved with low mortality and acceptable morbidity. Most significant complications are related to arrhythmias.

The pediatric electrocardiogram part III: Congenital heart disease and other cardiac syndromes

Approximately 1% of newborns are affected by congenital heart disease (CHD), and although many lesions of CHD have trivial hemodynamic and clinical implications, some clinically significant lesions are asymptomatic in the immediate newborn period and may present after discharge from the well baby nursery. Because of this, CHD should be considered in the differential diagnosis of any ill-appearing newborn, regardless of the presence of cyanosis. In addition, the number of children, adolescents, and adults with surgically repaired or palliated CHD continues to grow within the United States and other developed countries. It is in this population that arrhythmias are particularly prone to develop, and knowledge of the common arrhythmias associated with CHD is mandatory for the acute care provider.