Echocardiographic imaging and ventricular mechanics in pulsatile-flow LVAD pediatric patients: a systematic approach.

Echocardiography plays a crucial role in determining the eligibility for left ventricular assist device (LVAD) placement in patients experiencing advanced heart failure (HF) and in monitoring patient care after the implantation procedure. Because of its unique nature, pediatric population and pulsatile-flow LVADs used in pediatrics require specific skills so that pediatric echocardiographers must develop a systematic approach in order to image the patients pre and post LVAD implantation. Therefore, the purpose of this narrative review is to delineate a systematic echocardiographic approach for pediatric patients supported by pulsatile-flow LVADs.

Evolution of Ventricular Energetics in the Different Stages of Palliation of Hypoplastic Left Heart Syndrome: A Retrospective Clinical Study.

Hyperplastic left heart syndrome (HLHS) patients are palliated by creating a Fontan-type circulation passing from different surgical stages. The aim of this work is to describe the evolution of ventricular energetics parameters in HLHS patients during the different stages of palliation including the hybrid, the Norwood, the bidirectional Glenn (BDG), and the Fontan procedures. We conducted a retrospective clinical study enrolling all HLHS patients surgically treated with hybrid procedure and/or Norwood and/or BDG and/or Fontan operation from 2011 to 2016 collecting echocardiographic and hemodynamic data. Measured data were used to calculate energetic variables such as ventricular elastances, external and internal work, ventriculo-arterial coupling and cardiac mechanical efficiency. From 2010 to 2016, a total of 29 HLHS patients undergoing cardiac catheterization after hybrid (n = 7) or Norwood (n = 6) or Glenn (n = 8) or Fontan (n = 8) procedure were retrospectively enrolled. Ventricular volumes were significantly higher in the Norwood circulation than in the hybrid circulation (p = 0.03) with a progressive decrement from the first stage to the Fontan completion. Ventricular elastances were lower in the Norwood circulation than in the hybrid circulation and progressively increased passing from the first stage to the Fontan completion. The arterial elastance and Rtot increased in the Fontan circulation. The ventricular work progressively increased. Finally, the ventricular efficiency improves passing from the first to the last stage of palliation. The use of ventricular energetic parameters could lead to a more complete evaluation of such complex patients to better understand their adaptation to different pathophysiological conditions.

Ventricular assist devices as a bridge to heart transplantation or as destination therapy in pediatric patients.

PURPOSE: Despite the remarkable advances with the use of ventricular assist devices (VAD) in adults, pneumatic pulsatile support in children is still limited. We report on our experience in the pediatric population. METHODS: Retrospective review of 27 consecutive children offered mechanical support with Berlin Heart as a bridge to heart transplant, and Jarvik 2000 as a destination therapy from February 2002 to October 2011. RESULTS: The median patient age was 4.8 years (range = 75 days to 20.5 years). The median patient weight was 18.6 kg (range = 2.9-63 kg). We divided the patients in two groups, including in group I patients assisted for bridging to heart transplantation and in group II patients with Duchenne's dystrophy assisted as destination therapy. In the group I, 11 patients required biventricular mechanical support (BVAD), but in all other cases, a single left VAD proved sufficient (56%). The median duration of VAD support was 48 days (1 to 192 days). The median pre-VAD pulmonary vascular resistance index (Rpi) was 5.7 WU/m(2) (3.5 to 14.4 WU/m(2)). Twelve patients (48%) were successfully bridged to heart transplantation after a median duration of mechanical support of 63 days (range = 2-168 days). Ten deaths occurred (40%), three for neurological complications, two for sepsis, two for multiorgan failure, and three other for device malfunctioning. Since 2007, the survival rate of our patients has increased from 33% to 75%, and the need for BVAD has decreased from 89% to 23%. In the group II, two patients with mean age of 15.3 years were assisted with Jarvik 2000, and both of them are alive in a follow-up of 10.4 months. In two patients with Rpi > 10 WU/m(2), unresponsive to pulmonary vasodilatator therapy, Rpi dropped to 2.2 and 2 WU/m(2) after 40 and 23 days of BVAD support, respectively. Six patients (32%) required at least one pump change. Of 12 patients undergoing heart transplantation, five developed an extremely elevated (>60%) panel-reactive antibody by enzyme-linked immunosorbent assay, confirmed by Luminex. All of them experienced at least one acute episode of rejection in the first month after heart transplant, needing plasmapheresis. The survival rate after heart transplantation was 100% with a median follow-up of 34.4 months (45 days to 8.7 years). CONCLUSIONS: Mechanical support in children with end-stage heart failure is an effective strategy as a bridge to heart transplantation with a reasonable morbidity and mortality. BVAD support may offer an additional means to reverse extremely elevated pulmonary vascular resistance. The total implantable system opens a future scenarios for patients not eligible for heart transplantation.

Role of tricuspid regurgitation in fetal echocardiographic diagnosis of pulmonary atresia with intact ventricular septum.

OBJECTIVE: Pulmonary atresia with intact ventricular septum (PAIVS) is a rare cardiac malformation with a broad spectrum of anatomical manifestations, varying from types suitable for biventricular repair to those with diminutive right ventricle and primitive ventriculocoronary connections (VCC), more suitable for single-ventricle palliation or heart transplantation. We sought to test whether tricuspid regurgitation is an easily detectable prenatal criterion with which to identify PAIVS patients at lower risk of needing postnatal single-ventricle palliation. METHOD: We identified retrospectively patients with both fetal diagnosis and postnatal confirmation of PAIVS who were seen at Bambino Gesù Hospital between January 2000 and December 2006. Tricuspid valve/mitral valve (TV/MV) ratio, presence and severity of tricuspid regurgitation and direct visualization of VCC were evaluated by echocardiography both pre- and postnatally. RESULTS: We identified 22 patients with a prenatal diagnosis of PAIVS. Four pregnancies were terminated and one fetus was lost to follow-up, leaving 17 patients for the analysis. Based on postnatal cardiac catheterization and/or echocardiography we divided our population in two groups: Group 1 included 10 patients with VCC; Group 2 included seven patients without VCC. At fetal echocardiography, tricuspid regurgitation was absent in all ten Group 1 patients and present in all seven Group 2 patients. VCC were seen directly in 6/10 Group 1 patients and in no Group 2 patients. A cut-off value of 0.56 for the TV/MV ratio was highly predictive of VCC during fetal life, with a sensitivity of 100% and a specificity of 90%. CONCLUSIONS: The absence of tricuspid regurgitation in fetuses affected by PAIVS is a strong prenatal echocardiographic predictor of VCC, as is a TV/MV ratio < 0.56. Fetuses presenting with tricuspid regurgitation and relatively large right ventricle are at lower risk of needing single-ventricle palliation postnatally. This inforation could be helpful for appropriate prenatal counseling and postnatal decision-making.