Right Ventricular Overload Due to Severe Pulmonary Valve Regurgitation in 44-Year-Old GUCH.

Notoriously, the valvular disease of the right heart have always received less attention than the left heart valvular disease both by echocardiographers and by researchers, probably due to the long period of latent asymptomatic and for the intrinsic difficulties of examination. However, it is increasingly recognized that right-sided valve disease is not a benign lesion and has a significant and independent impact on morbidity and mortality. Pulmonary regurgitation (PR) is common after surgical or percutaneous relief of pulmonary stenosis and following repair of tetralogy of Fallot. This case report describes the natural history of an adult patient with grown-up congenital heart (GUCH) who became competitive athlete and who showed signs of extreme morphological and functional adaptation of the right heart resulting in the outcome of a previous run surgical valvotomy at the age of 5 years for a congenital pulmonary stenosis. These anatomic changes of the right ventricle and pulmonary circulation have requested the replacement of the pulmonary valve for the symptomatic pulmonary hypertension, with subsequent gradual return to sports activity.

INTRODUCTION

Notoriously, the valvular disease of the right heart have always received less attention than the left heart valvular disease both by physicians and by researchers, probably due to the long period of latent asymptomatic.[1] However, it is increasingly recognized that right-sided valve disease is not a benign lesion and has a significant and independent impact on morbidity and mortality.[2] Right ventricular (RV) volume overload is commonly caused by pulmonary or tricuspid regurgitation, or an atrial septal defect (not ventricular septal defect, as this presents the right ventricle with increased blood volume only after the onset of systole, therefore end-diastolic volume remains normal). Pulmonary regurgitation (PR) is common after surgical or percutaneous relief of pulmonary stenosis and following repair of tetralogy of Fallot. Despite PR is well-tolerated in childhood, recent data have demonstrated that PR leads to progressive RV dilatation and eccentric hypertrophy, and with time, to RV dysfunction, exercise intolerance, ventricular arrhythmias, and rarely sudden cardiac death (SCD).[34] In adults, pathological PR most often is the consequence of prior intervention for congenital heart disease such as tetralogy of Fallot repair with placement of an outflow tract patch[5] or surgical valvotomy for isolated congenital pulmonary stenosis (PS).[6] PR also can occur secondary to pulmonary hypertension (PHT). Patients with long standing severe PR develop progressive RV dilatation and consequently reduced RV function, as what happens to patients undergoing valvolotomy surgery for congenital isolated valvular stenosis. This can lead to inability to improve cardiac output with exercise and this inability can precipitate heart failure. In addition, the dilated and dysfunctional RV is associated with QRS prolongation, ventricular arrhythmias, and rarely SCD.[1]

CASE REPORT

This case report concerns a 44-year-old competitive cyclist that comes at our medical center for sports pre-participation screening. The peculiarity is that this athlete is a grown-up congenital heart (GUCH) disease, in fact for the detection of congenital pulmonary valve stenosis at age 5 was subjected to surgical valvotomy. The controls of physical fitness and eligibility to competitive sports in previous years were normal and even recent echocardiographic examinations performed at other centers signaled only a moderate degree of pulmonary insufficiency and mild dilatation of the right chambers heart. However, a few months this athlete refers to accuse episodes of palpitations during intense physical exertion for which it wishes to undergo more precise findings. The physical examination revealed rhythmic heart sounds, which are valid with a palpable pulmonic component (P2) of the second heart sound (S2) at the left upper sternal border and a sustained RV impulse that is increased in amplitude at the left middle and lower sternal border. On auscultation, the first heart sound (S1) is normal, but was present a high-pitched, early diastolic decrescendo murmur that begins with P2 and ends before S1 and that radiates toward the mid-right sternal edge (Graham Steell murmur), as typical findings of PR. The peripheral pulses were synchronous. The resting ECG showed sinus rhythm, a complete RV conduction delay (right bundle branch block) and signs of overload. A two-dimensional (2D) transthoracic echocardiographic examination, performed with the instrument EsaOte MyLab 30 Gold, showed a markedly hypertrophied [Figure 1 - Panel d] and dilated right ventricle [Figure 1 - Panel a and b] globally by severe pulmonary valve insufficiency [Figure 2 - Panel b and c] with pressure equalization between RV and pulmonary artery in mid diastole. The estimation of the mean pulmonary artery pressure of 45 mmHg resulted, calculated by the acceleration time of the pulmonary flow and the presence of mid-systolic notching [Figure 2 - Panel d] with dilated trunk of mean pulmonary artery [Figure 2 - Panel a] and of the velamentous cord insertion (VCI) with reduced respiratory excursions and collapsibility <50%. In addition, there was a mild impairment of the RV contractility and systolic function with the presence of LV flattening-D shape morphology [Figure 1 - Panel c] in the parasternal short-axis with index of eccentricity equal to about 1.6-1.7 at end-diastole (volume overload). It was also a mild tricuspid regurgitation due to annulus dilatation of tricuspid valve. Vice versa the LV diameters and morphology was normal with preserved global contractility. Finally, it has been diagnosed moderate pulmonary hypertension (group 1) to severe pulmonary insufficiency and subsequent expansion of the RV for volume overload, symptomatic arrhythmias inducible by exercise, high risk. Consequently both thoracic computed tomography (CT) and angiography of the pulmonary artery is more a CMR confirmed both cardiac structural abnormalities secondary to functional RV overload, in particular the marked dilatation with hypertrophy of the right ventricle, due to PR with a dilated size of the annulus of pulmonary valve that caused severe pulmonary insufficiency. Namely the expansion of the right heart and main pulmonary artery and pulmonary artery dx, straightening of the interventricular septum, all suggestive of a radiological signs compatible with pulmonary hypertension. All these findings confirmed the echocardiographic features and diagnosis. A further lung scan excluded the presence of pulmonary embolism and showed an increase in vascularity of hypertension typical of the small circle. A further angiography showed normal coronary tree. All these clinical and instrumental data posed indication to pulmonary valve replacement, which was then carried out with homograft valve getting a good result.

Figure 1

Panel a and Panel b shows respectively right ventricular (RV) and outflow tract enlargement due to volume overload in apical four chamber view and parasternal long-axis view (PLAX) view; Panel c shows typical left ventricular eccentricity index in parasternal short-axis view (PSAX) view; Panel d shows moderate thickening of the right ventricle free wall hypertrophy in subcostal long axis view

Figure 2

Panel a shows a significant dilated trunk of the main pulmonary artery; Panel b shows a pulsed-wave (PW) spectral Doppler of severe pulmonary regurgitation; Panel c shows a M-mode color Doppler of severe pulmonary regurgitation; Panel d shows a typical pattern of PW Doppler acceleration time of pulmonary flow with mid-systolic notching

CONCLUSIONS

It’s now clear that the chronic PR causes RV volume overload with deleterious effects on the function and exercise capacity, but also an increased likelihood of threatening ventricular arrhythmias and sudden death. In our time more and more patients with previous GUCH valvotomy for congenital pulmonary stenosis become candidates for replacement of the pulmonary valve, which must be made promptly and before the dysfunction of the right ventricle becomes irreversible. This case report shows the effectiveness and the outcomes of an early diagnosis.