Impaired atrioventricular transport in patients with transposition of the great arteries palliated by atrial switch and preserved systolic right ventricular function: A magnetic resonance imaging study

Overview of Long-Term Outcome in Adults with Systemic Right Ventricle and Transposition of the Great Arteries: A Review

The population of patients with a systemic right ventricle (sRV) in biventricular circulation includes those who have undergone an atrial switch operation for destro-transposition of the great arteries (d-TGA) and those with congenitally corrected transposition of the great arteries (ccTGA). Despite the life expectancy of these patients is significantly increased, the long-term prognosis remains suboptimal due to late complications such as heart failure, arrhythmias, and premature death. These patients, therefore, need a close follow-up to early identify predictive factors of adverse outcomes and to implement all preventive therapeutic strategies. This review analyzes the late complications of adult patients with an sRV and TGA and clarifies which are risk factors for adverse prognosis and which are the therapeutic strategies that improve the long-term outcomes. For prognostic purposes, it is necessary to monitor sRV size and function, the tricuspid valve regurgitation, the functional class, the occurrence of syncope, the QRS duration, N-terminal pro B-type natriuretic peptide levels, and the development of arrhythmias. Furthermore, pregnancy should be discouraged in women with risk factors. Tricuspid valve replacement/repair, biventricular pacing, and implantable cardioverter defibrillator are the most important therapeutic strategies that have been shown, when used correctly, to improve long-term outcomes.

The association between myocardial ischemia and myocardial dysfunction in adult patients with systemic right ventricle - A single centre multimodality study

BACKGROUND

The exact interaction of factors leading to myocardial dysfunction and fibrosis of the systemic right ventricle (SRV) is not completely understood. Myocardial ischemia and injury associated with a supply-demand mismatch of the pressure overloaded SRV are thought to play an important role, however studies confirming this are lacking.

METHODS

Adult SRV patients were included in this single centre cohort study. All patients underwent a comprehensive diagnostic and imaging workup. A two-day stress-rest SPECT was performed to assess myocardial perfusion. SRV ischemia was defined as decreased segmental tracer uptake during exercise with significant improvement at rest. Contrast enhanced cardiac magnetic resonance imaging (CMR) was also performed in a subgroup of patients without contraindication, to assess focal myocardial fibrosis. Differences between patients with and without SRV ischemia were assessed.

RESULTS

Twenty-three SRV patients (15 with transposition of the great arteries after atrial switch procedure and 8 with congenitally corrected transposition of the great arteries; 5 (22%) females; mean age 38 ± 11 years) were included. Seven (30%) patients had SRV ischemia on SPECT. Late gadolinium enhancement on CMR was more common in patients with SRV ischemia (p = 0.002). However, there was no association between SRV ischemia and different echocardiographic or CMR parameters of SRV systolic function, laboratory markers (high-sensitivity troponin I and NT-proBNP) and exercise capacity.

CONCLUSIONS

Our multimodality study showed that SRV ischemia in adult SRV patients was associated with more focal myocardial fibrosis, but not with functional or imaging markers of SRV function.

Impact of pregnancy on natural history of systemic right ventricle in women with transposition of the great arteries

In the recent years, the pregnancy trend among women with Congenital Heart Disease (CHD) has increased; this has leaded to a growing demand for specialized care both in mother and in children. Although pregnancy is often well tolerated, maternal CHD may affect in some cases a maladaptive hemodynamic response carrying additional risks of cardiovascular events like arrhythmias, heart failure and, in rare cases, death. The impaired utero-placental perfusion due to maternal cardiac status may result in placental dysfunction, which may be associated with fetal growth restriction, preeclampsia, premature birth and perinatal morbidity. Systemic Right Ventricle (SRV) is one of the main conditions under which pregnancy is challenging. The sub-aortic position of morphological Right Ventricle (RV) is "physiologically" predisposed to fail at the adult age and may be potentially inadequate to support the hemodynamic stress of the pregnancy. Current literature about pregnancy in women with SRV consists of small retrospective series not providing conclusive evidence about the feasibility of a successful pregnancy outcomes. In addition, the long-term effects of pregnancy on SVR are not still adequately investigated and it remains unclear if maternal complications reported are due to pregnancy or to natural history of SVR. The aim of this paper is to offer a critical review of the knowledges at regard and to provide a practice update on the risk assessment and the pregnancy management in women with SRV in order to support the decision making and to optimize outcomes in these patients.

Clinical and Echocardiographic Predictors of Outcomes in Patients With Pulmonary Hypertension

In pulmonary hypertension (PH), measurement of various echocardiographic parameters that assess right heart function is recommended by current clinical guidelines. Limited data exists on the combined value of clinical and echocardiographic parameters in precapillary PH in the modern era of therapy. We examined the association of clinical and echocardiographic parameters with surrogate outcomes (6-minute walk distance) and hard outcomes (hospitalization or death) in patients with precapillary PH. A cohort of patients with an established diagnosis of precapillary PH who underwent transthoracic echocardiography at the Duke Echo Lab were prospectively enrolled from 2010 to 2014. Univariable and multivariable models were constructed to examine the relation of clinical and echocardiographic parameters with surrogate and hard outcomes. Of the 98 patients with analyzable echocardiograms with good image quality, 85 were woman, mean age was 59.4 years, and 47% had ≥World Health Organization functional class III symptoms. The mean 6-minute walk distance was 354(±132) m, and 83% were on pulmonary arterial hypertension medications. At 24 months, the cumulative incidence rate for hospitalization or death was 47%. In univariable analyses, the REVEAL (Registry to Evaluate Early and Long-term PAH Disease Management) risk score (HR 1.72 per 1 SD (2.81) increment, 95% CI 1.34, 2.22; p=<0.001), RV global longitudinal strain (RVGLS) (HR 1.54 per 1 SD (5.31) worsening, 95% CI , 2.12; p=0.008) and log-2 NT proBNP (HR 1.43 per 1-fold increase, 95% CI 1.25, 1.63; p=<0.001) were significantly associated with hospitalization or death.