The Electrocardiogram in Tricuspid Atresia and Pulmonary Atresia with Intact Ventricular Septum

Abstract

Electrocardiograms were studied in 37 patients with tricuspid atresia and in 20 with pulmonary atresia and intact ventricular septum. The results were correlated with angiocardiographic findings and postmortem examinations. Differential features were as follows: 1. Biatrial hypertrophy with characteristic P "tricuspidale" was noted in 81% of the electrocardiograms in patients with tricuspid atresia, whereas this pattern was seen in only two infants with pulmonary atresia and intact ventricular septum. 2. In tricuspid atresia, left axis deviation was usually directed posteriorly; however, anmal or right axis deviation was present in seven cases, six of whom were type 2C and the seventh, type 1A. In every case the horizontal QRS axis was oriented posteriorly. By contrast, in patients with pulmonary atresia there were no instances of left axis deviation in the frontal plane. Normal frontal plane axis was present in 12 patients, all of whom were type I; right axis deviation was evident in eight patients including the three infants with type II deformity. The horizontal QRS axis was usually directed posteriorly; however, anterior orientation occurred in several patients. 3. A typical feature of the vectorcardiogram in patients with tricuspid atresia was the increased anterior magnitude of the initial forces followed by a sharp posterior shift. The initial forces in patients with pulmonary atresia were not characteristic. 4. The electrocardiographic features in patients with tricuspid atresia and normal position of the great vessels showed decreased right ventricular potentials consistent with true hypoplasia of the right ventricle, but in patients with pulmonary atresia similar lack of right ventricular potentials could be correlated with decreased right ventricular cavity, whereas the ventricular wall was actually hypertrophied.

Atrioventricular conduction tissues in univentricular hearts of left ventricular type with absent right atrioventricular connection ('tricuspid atresia').

“…An anomalous course of the left bundlebranch was suspected by Gamboa et al (1966) and this concept was supported by the findings of Guller et al (1969). Our findings are in keeping with those of Guller et al (1969) and further support the concept of an abnormal distribution of the left bundle-branch.…”

Tricuspid Atresia and Ventricular Septal Defect in a 31-year-old Woman

“…However, it may also he due to a transposition of the vena cava inferior with open ing into the left atrium [ [1950] point out that an axis devia tion to the right does not exclude TA. Other frequent electrocardio graphic features are tall and peaked P waves in the standard leads and in V, to V:1, a delay of the inlrinsicoid deflection in the left unipolar precordial leads, and evidence of the left ventricular dominance [2,14,20,21,26]. Figures la and b show that the characteristic changes seen in the EGG were also noted in our patient.…”

Tricuspid atresia. Clinical course in 62 cases (1967--1974).

“…Twentyfour patients with type I atresia (61 5%) had superior and left axis, while only 5 (22 7%) with type II atresia had a superior axis. In our series'a superior and left axis occurred in relatively fewer patients than in those previously reported (Gamboa et al, 1966;Davachi et al, 1970). However, signs l of left ventricular hypertrophy in the praecordial leads were present in 92 per cent of cases.…”