Right ventricular function and ventricular perfusion defects in adults with congenitally corrected transposition: correlation of echocardiography and nuclear medicine

Abstract

We undertook our study in order to evaluate right ventricular function and perfusion by conventional and contrast echocardiography in adults with congenitally corrected transposition who had not undergone cardiac surgery, comparing the echocardiographic findings with those obtained using equilibrium radionuclide ventriculography and gated single-photon emission computed tomography with Technetiumc-99 m sestamibi. We discovered severe tricuspid regurgitation in 8 patients (61%). Right ventricular ejection fraction, as calculated by nuclear medicine, had a correlation of 0.67 (p = 0.059) with area fractional shortening and 0.84 (p = 0.01) with ejection fraction calculated by the method depending on descent of the tricuspid ring. All patients with severe tricuspid regurgitation also had right ventricular dysfunction. Of these 8 patients, 7 had persistent perfusion defects, while 6 also had ischemic perfusion defects. Echo contrast had a high sensitivity, at 91%, and also specificity and positive predictive value, both at 100%, for persistent defects, and a negative predictive value of 66% compared to methods depending on nuclear medicine. The sensitivity of contrast echocardiography for detection of ischemic defects was 66%, the specificity 100%, the positive predictive value 100%, and the negative predictive value 77% compared to the methods involving nuclear medicine. The method depending on descent of the tricuspid ring had the highest correlation with equilibrium radionuclide ventriculography in evaluation of right ventricular function in patients with congenitally corrected transposition. We conclude that contrast echocardiography is extremely valuable when assessing right ventricular myocardial perfusion, having high sensitivity and specificity for detecting persistent defects, although sensitivity was less for detection of ischemic defects than that of gated single-photon emission computed tomography with Technetium-99 m Sestamibi. Persistent and ischemic perfusion defects, together with chronic volume overload from tricuspid regurgitation, are the determining factors of right ventricular dysfunction.

Interest of β-blockers in patients with right ventricular systemic dysfunction

“…In patients with congenitally corrected transposition or transposition after Mustard or Senning operation, ischaemic perfusion defects, together with chronic volume overload from tricuspid regurgitation and long-standing pressure overload, are the determining factors of right ventricular dysfunction. [15][16][17][18] Moreover, cardiopulmonary bypass with inflammatory mediators and hypothermic circulation arrest (often multiple exposure), tricuspid valve surgery, significant arrhythmia, and pacemaker therapy are well-known risk factors for systemic right ventricular dysfunction. 2,19 Interestingly, Doughan et al 20 has also reported that b-blockers, carvedilol or metoprolol, in patients with transposition and systemic right ventricular dysfunction resulted in improvement of New York Heart Association functional class and such improvement was more important in patients with pacemakers who could receive higher maintenance doses of b-blockers.…”

Physiologic Repair of Congenitally Corrected Transposition of the Great Arteries

“…In addition, poor tolerance of the systemic AV valve to systemic pressure after VSD closure is possible because afterload is increased, and postoperative complete AV block may compound the adverse hemodynamics. The observation of progressive systemic AV valve regurgitation after operative intervention has prompted some authors to recommend systemic AV valve replacement at the time of intracardiac repair if the systemic AV valve regurgitation is moderate or more at the time of surgery [ 26 ].…”

Canadian Cardiovascular Society 2009 Consensus Conference on the management of adults with congenital heart disease: Complex congenital cardiac lesions

“…Le document complet et les références figurent également aux adresses www.ccs.ca et www.cachnet.org. course of coronary arteries are present in one-third of patients, and an intramural coronary artery course is present in 3% to 4% (1,2).…”