Factors influencing longevity in adults with congenital complete heart block

Congenital complete heart block in patients without anatomic cardiac defects

Forty-three patients with congenital complete heart block and an otherwise structurally normal heart were reviewed in an effort to better define the profile of an anatomically homogenous group and to identify factors that may predict the need for pacing. Fourteen patients (32%) developed "symptoms" during follow-up, including two with out-of-hospital cardiac arrest. Heart rate on electrocardiogram or Holter monitor did not clearly distinguish this subgroup. The presence of alternate "risk factors," such as atrial enlargement seen on electrocardiogram, cardiomegaly seen on x-ray film, or prolonged QT interval were independent predictors of symptoms and poor outcome (p less than 0.05). Ventricular ectopy determined on Holter monitoring was also common among the symptomatic group, although this finding was inconsistent. Prophylactic pacing is indicated in select patients with congenital complete heart block and otherwise normal anatomy. Surveillance for rick factors beyond rate criteria alone may refine this selection process.

Fatal heart block due to mesothelioma of the atrioventricular node

A fit young man of 23 was symptom free until the time of his death despite a narrow complex complete heart block, with resting heart rates down to 35 beats/min, that was first diagnosed when he was 10. The clinical diagnosis remained congenital heart block. Necropsy showed extensive infiltration of the atrioventricular node and proximal bundle by mesothelioma tissue. Pacing had not been advised because of his excellent exercise tolerance.

Left ventricular function at rest and during exercise in congenital complete heart block: a radionuclide angiographic evaluation

This study evaluates intrinsic cardiac performance during upright exercise in patients with congenital complete heart block. Left ventricular ejection fraction and volume were measured at rest and peak upright exercise with radionuclide angiography in 5 patients aged 11 to 39 years with congenital complete heart block: 4 were in New York Heart Association class I and 1 was in class II. The resting cardiac output was maintained at a normal level by an increase in end-diastolic volume rather than by a decrease in end-systolic volume. The left ventricular ejection fraction was normal at rest in all patients, but an abnormal response to exercise was noted in 3 patients. There was no appreciable change in the end-diastolic volume during exercise. Thus, patients with congenital complete heart block utilize the Starling mechanism to maintain normal resting cardiac output, but the response to exercise is usually abnormal even in the absence of symptoms.

Long-term follow-up of young adults following permanent pacemaker placement for complete heart block

Young adults with nonsurgically induced complete heart block (CHB) do not necessarily have a benign prognosis and pacemaker (PM) implantation may be necessary. No one has reported long-term PM follow-up in young adults with CHB. We studied 13 patients aged 15 to 37 years (mean 24 years) at PM implantation. There were nine female and four male patients. All were functional class II or III (NYHA) before PM implantation. Syncope, dizziness, fatigue, shortness of breath, and dyspnea on exertion were the most common symptoms. Cardiac catheterization findings (11 of 13 patients) were normal in five, and additional cardiac anomalies were present in six. His bundle studies (9 of 13 patients) showed absent AH intervals in all patients, with HV intervals not identified in two, 20 to 30 msec in one, and 30 to 50 msec in six patients. Holter monitor recordings (8 of 13 patients) demonstrated CHB in all eight with intermittent second- to third-degree block in two of three patients. Two patients had occasional premature ventricular contractions. Stress exercise tests (9 of 13 patients) demonstrated increased ventricular rate response (although subnormal in some patients); symptoms developed in seven. One patient had ventricular ectopy. All 13 patients were contacted 3 months to 7 years (mean 4 years) after PM implantation. Two patients had died, but the deaths were not related to PM dysfunction. All patients who are currently alive had marked improvement in functional symptomatology and all are currently functional class I. CHB is not a benign condition in young adults and may require PM implantation, which improves symptoms and allows the patient to lead a normal life.