Preserved Ventricular Function Research Articles

Velocidad media de la arteria pulmonar estimada por resonancia magnética cardiaca como predictor pronóstico precoz en insuficiencia cardiaca

Background and objectiveTo identify early, non-invasive prognostic indicators in heart failure (HF), with and without associated pulmonary hypertension, by means of cardiac magnetic resonance, and oxidative stress and anti-inflammatory biomarkers such as TroloxTM (antioxidant status) and IL-10 (anti-inflammatory cytokine). Patients and methodsWe prospectively included 70 patients admitted for new-onset HF. During index admission, mean velocity of the pulmonary artery (mvPA) was measured, and blood TroloxTM and IL-10 determined. The study sample was divided in two groups according to the optimal cut-off value for event prediction calculated by the ROC curve (mvPA=8cm/s), considering HF-readmission and all-cause mortality as the primary combined event. ResultsDuring a median follow-up of 290 days, 16 events occurred. In patients with preserved right ventricular (RV) function, mvPA ≤8cm/s was associated with a higher incidence of events during follow-up, Kaplan-Meier survival analysis (log rank 6.01, p=.014). MvPA did not add prognostic value when RV dysfunction was already established. TroloxTM concentration was lower in patients with mvPA ≤8cm/s. Higher IL-10 expression was associated with a lower incidence of cardiovascular events during follow-up. ConclusionIn HF patients, mvPA ≤8cm/s predicts a higher rate of cardiovascular events. Specifically, mvPA identifies a higher risk population among patients with preserved RV function, thus confirming its role as an early prognostic indicator. Lower TroloxTM concentration in the worse prognosis group concurs with previous studies on oxidative stress in pulmonary hypertension. Higher IL-10 concentration among patients free of cardiovascular events could be a reflection of its anti-inflammatory and thus protective role in HF.

The effect of right ventricular function on survival and morbidity following stage 2 palliation: An analysis of the single ventricle reconstruction trial public data set.

Limited information is known on how right ventricular function affects outcomes after stage 2 palliation. We evaluated the impact of different right ventricular indices prior to stage 2 palliation on morbidity and mortality. Retrospective study design. Pediatric Heart Network Single Ventricle Reconstruction Trial Public Data Set. Any variant of stage 1 palliation and all anatomic hypoplastic left heart syndrome variants in the trial were evaluated. Echocardiograms prior to stage 2 palliation were analyzed and compared between those who failed and those who survived. None. Mortality was defined as death, listed for transplant, or transplanted after stage 2 palliation. Morbidity was evaluated as hospital length of stay and duration of intubation. A total of 283 patients met criteria for analysis. Of those, only 18 patients failed stage 2. Right ventricular fractional area change was less in those who failed (30% vs 34%, P=.039) and right ventricular indexed end-diastolic volume and end-systolic volume were larger in those who failed (142.74 mL/ BSA1.3 vs 111.29 mL/BSA1.3 , P=.023, 88.45 mL/ BSA1.3 vs 62.75 mL/ BSA1.3 , P=.025, respectively). Larger right ventricular indexed end-diastolic and systolic volumes were associated with failure (OR 1.17 [1.01-1.35] P=.021, OR 1.25 [1.03-1.52] P=.021, respectively). Every 10% increase in RV ejection fraction had a 63% decrease in length of stay and a 68% decrease in duration of intubation (P=.014, and P=.039, respectively). Patients with decreased right ventricular fractional area change and larger right ventricular indexed end-diastolic and systolic volumes were more likely to fail stage 2 palliation. Those with preserved right ventricular function had a shorter hospital length of stay and duration of intubation. Echocardiographic measurements of right ventricular indices during the interstage period can be utilized to determine the prognosis following stage 2 palliation.

Hemodynamic target variables in the intensive care unit

Despite broad availability, extended hemodynamic monitoring is used in practice only in the minority of critical care patients. Pathophysiological reasoning suggests that systemic perfusion pressure (and thereby arterial as well as central venous pressure), cardiac stroke volume, and the systemic oxygen balance are key variables in maintaining adequate organ perfusion. In line with these assumptions, several studies support that agoal-directed optimization of these hemodynamic variables leads to areduction in morbidity and mortality. The appropriate monitoring modality should be selected following echocardiographic evaluation of biventricular function. Ideally, high-risk patients with limited right ventricular function should be monitored with apulmonary artery catheter. In patients with preserved right ventricular function, transpulmonary thermodilution with special consideration of extravascular lung water seems to be sufficient to guide hemodynamic therapy.

Mitral valve repair versus replacement for patients with preserved left ventricular function without heart failure symptoms

ObjectiveThe purposes of this study are to compare outcomes of mitral valve repair (MV-repair) and mitral valve replacement for patients with severe mitral regurgitation with preserved ventricular function and no congestive heart failure (CHF) symptoms and to examine variations in surgeon choice of procedure and outcomes by surgeon volume. MethodsIn total, 2259 consecutive patients in 42 New York State hospitals with the characteristics mentioned previously who underwent mitral valve repair (1801, 79.7%) or replacement between January 1, 2008, and December 31, 2014, were identified from a mandatory statewide clinical registry. Propensity-matching was used to compare mortality and competing risk analyses were used to compare nonfatal outcomes. Median follow-up was 4.0 years. The use of mitral repair and risk-adjusted mortality for surgery were also examined as a function of individual surgeon mitral case volume. ResultsPropensity-matched patients who underwent MV-repair experienced a significantly lower mortality rate at 4 years (3.5% vs 12.1%, P < .001). Greater-volume surgeons were more likely to perform MV-repairs (92% vs 84%, 74%, and 69% in lower volume quartiles, respectively). No significant differences in mortality were observed among volume quartiles. ConclusionsPatients with chronic severe primary mitral valve regurgitation with preserved ventricular function and no CHF symptoms who underwent MV-repair experienced lower mortality and no different reoperation, CHF, or stroke readmission rates than patients who underwent replacement. Greater-volume surgeons were more likely than their lower volume counterparts to choose mitral repair. Repair should be considered as the surgical option for these patients whenever possible.

Advances in heart failure therapy in pediatric patients with dilated cardiomyopathy.

While in adults major advances in heart failure therapy in patients with dilated cardiomyopathy were documented in the last two decades, research on the mechanism and therapies of heart failure in children with left ventricular dilated cardiomyopathy has lagged behind. Despite the lack of sufficient randomized prospective studies, ACE inhibitors are first line and ß-receptor antagonists are second-line strategies in children. Following the adult guidelines, without having data concerning the pediatric population, mineral corticoids are also accepted in the treatment of pediatric heart failure, while diuretics should only be used to achieve a euvolemic status. In cases of complete left bundle bunch block or prolonged QRS duration, cardiac resynchronization is an option. If these instruments are exploited, and the child is still listed for heart transplantation as destination, evolving therapies like pulmonary artery banding in cases of preserved right ventricular function and cardiac cell therapy in cases of localized ventricular dysfunction might represent additional treatment options. This review summarizes the actual guidelines and provides an outlook for evolving therapies.

Primary pulmonary arterial hypertension with preserved right ventricular function leads to lower extremity venous insufficiency.

Objectives Pulmonary hypertension with heart failure is related to venous insufficiency. However, there is no clear data whether pulmonary arterial hypertension with preserved right ventricular function cause venous insufficiency. In this study, we aim to investigate the relation between pulmonary arterial pressure with venous insufficiency in pulmonary arterial hypertension patients with preserved right ventricular function. Methods Between January 2012 and October 2014, 38 patients with a diagnosis of pulmonary arterial hypertension and 47 control group patients were included. Venous disability score and venous segmental disease score of both groups were calculated in order to measure venous insufficiency. The relationship between venous disability score and venous segmental disease scores and mean pulmonary arterial pressure and World Heart Organization functional capacity was examined. Results Total venous segmental disease score (5 ± 3.9 vs. 2 ± 1.8 p < 0.001), right venous segmental disease score (2.6 ± 2.2 vs. 1 ± 0.9 p < 0.001), left venous segmental disease score (2.4 ± 2.2 vs. 1 ± 0.9 p < 0.001), and venous disability scores (2.2 ±1 vs. 1.6 ± 0.7 p < 0.001) of patients with pulmonary arterial hypertension were higher than the control group. While the total venous segmental disease score was highly related to mean pulmonary arterial pressure (r = 0.829, p < 0.001), the venous disability score was only weakly related (r = 0.343, p = 0.037). Total venous segmental disease score (r = 0.606, p < 0.001) and venous disability scores (r = 0.601, p < 0.001) were moderately related with World Health Organization functional capacity intensity. Conclusions The degree of venous insufficiency increase in accordance with the mean pulmonary arterial pressure even in patients with preserved right ventricular function.

Early intracardiac thrombus and pulmonary embolus after trauma

Here, we present the case of a patient with the findings of an early intracardiac thrombus and a pulmonary embolus after major trauma. A large clot was identified extending from...

Abstract 11425: Left Ventricular Function and Coronary Artery Disease in Patients With and Without Diabetes. Long-term Follow-up - Revision-dm2 Trial

Introduction: It is assumed that the left ventricular dysfunction due to ischemic cardiomyopathy is a major determinant of poor prognosis of survival when compared to preserved ventricular function. However, it is unknown the role of diabetes in long-term prognosis in this patient group compared to patients without diabetes. Hypothesis: To investigate whether the presence of diabetes affects the prognosis in ventricular function in long-term follow-up. Methods: We prospectively analyzed in a database, outpatients, previously submitted to percutaneous, surgical or clinical treatment. All patients had multivessel disease and LVEF measures. The events considered were overall mortality, nonfatal myocardial infarction, stroke and additional interventions. Results: From January 2009 to January 2010 were selected 918 consecutive patients, followed until May 2015. They were grouped into: G1, 266 diabetic patients with ventricular dysfunction, G2, 213 diabetic without dysfunction, G3, 213 patients without diabetes and without dysfunction and G4, 226 patients without diabetes and with dysfunction. The mortality rate was 21.6%, 6.1%, 4.2% and 10.6% for Groups 1, 2, 3 and 4 respectively. (p &lt;0.001). The incidence of nonfatal myocardial infarction was 5.3%, 0.5%, 7.0% and 2.6% for groups 1, 2, 3 and 4 respectively (p &lt;0.001). Stroke occurred at 0.40% 0.45%, 0.90% and 0.90% in groups 1, 2, 3 and 4 respectively (p = NS). Further interventions occurred in 3.8%, 11.7%, 10.3% and 2.6% for groups 1, 2, 3 and 4 respectively (p &lt;0.001). Conclusion: In this sample, regardless of the treatment received, diabetes mellitus added higher risk of cardiovascular events in patients with coronary artery disease and left ventricular dysfunction.

Global Longitudinal Strain in master athletes and in hypertensive patients with the same degree of septal thickness.

Athletes may have electrocardiogram (ECG) repolarization abnormalities during stress test suggestive for ischemia in the absence of ischemic coronary artery disease, often in a setting of myocardial septum hypertrophy. Global longitudinal strain (GLS) might be altered in these athletes compared to hypertensive patients with the same degree of septal thickness. About 735 consecutive athletes were screened for mandatory assessment of fitness to participate in competitive sports. At the stress test, 23 (19 M, 4 F) were found to have ECG repolarization abnormalities suggestive for ischemia in the presence of normal coronary vessels. They were matched to a control group of 23 hypertensive patients with no ECG abnormalities during stress test and the same degree of septal thickness. A transthoracic echocardiography for evaluation of global longitudinal strain (GLS) was performed. Interventricular septum thickness (IST) and relative wall thickness (RWT) were also calculated. A preserved ventricular function was seen in both groups (64±8% in cases vs 60±6% in controls, P=0.42). IST and RWT were not significantly different. GLS was significantly lower in athletes vs hypertensive patients (-18.7±2.5 vs -21.67±0.27, P=0.001). In athletes with septal hypertrophy and a positive stress test not associated to coronary disease, GLS is lower with respect to a population of hypertensive patient with the same degree of septal hypertrophy. Further investigations in a larger population are required to better define the potentiality of GLS in differentiating pathological vs physiological septum hypertrophy.

Impact of mode of failure and end-organ dysfunction on the survival of adult Fontan patients undergoing cardiac transplantation.

Adults with failing Fontan circulation (FFC) represent a heterogeneous, high-risk group for cardiac transplantation with poor reported outcomes. We studied the impact of mode of Fontan failure (preserved versus impaired systolic ventricular function) and end-organ dysfunction on early survival in adults undergoing cardiac transplantation for FFC. A single-centre, retrospective study of 26 adults (≥16 years) with FFC undergoing cardiac transplantation between 1990 and 2015. Patients were classified by the presence or absence of preserved systolic ventricular function (PVF). End-organ dysfunction was assessed by serum markers, including albumin, liver ultrasound and the presence of varices, ascites, splenomegaly and thrombocytopaenia (VAST score for portal hypertension). Thirty-day survival rate for the entire cohort was 69.2%, with 76.2% survival for the recent era. One-year Kaplan-Meier survival rate was 65.4%. Actuarial survival was poorer in those with PVF or heterotaxy (P = 0.01; log-rank test). Cox multivariable regression analysis confirmed PVF as an independent predictor for death (odds ratio, OR 5.38; confidence interval, CI 1.08-26.96; P = 0.04). In examining the PVF subset further, these patients had significantly higher VAST and liver ultrasound scores and lower serum albumin, compared with patients with impaired function. Patients with PVF and ≥moderate liver fibrosis on ultrasound or VAST score ≥2 accounted for two-thirds of the total mortality. Favourable cardiac transplantation outcomes can be achieved in adults with failing Fontan circulation. Patients with PVF may represent a distinct subset with more perturbed failing Fontan physiology and higher cardiac transplant mortality. We continue, however, to evolve and refine our strategies and are optimistic concerning future improvement in outcomes even in those with PVF.

Improved survival after heart transplant for failed Fontan patients with preserved ventricular function

Patients with a failing Fontan continue to have decreased survival after heart transplant (HT), particularly those with preserved ventricular function (PVF) compared with impaired ventricular function (IVF). In this study we evaluated the effect of institutional changes on post-HT outcomes. Data were retrospectively collected for all Fontan patients who underwent HT. Mode of failure was defined by the last echocardiogram before HT, with mild or no dysfunction considered PVF and moderate or severe considered IVF. Outcomes were compared between early era (EE, 1995 to 2008) and current era (CE, 2009 to 2014). Management changes in the CE included volume load reduction with aortopulmonary collateral (APC) embolization, advanced cardiothoracic imaging, higher goal donor/recipient weight ratio and aggressive monitoring for post-HT vasoplegia. A total of 47 patients were included: 27 in the EE (13 PVF, 14 IVF) and 20 in the CE (12 PVF, 8 IVF). Groups were similar pre-HT, except for more PLE in PVF patients. More patients underwent APC embolization in the CE (80% vs 28%, p < 0.01). There was no difference in donor/recipient weight ratio between eras. There was a trend toward higher primary graft failure for PVF in the EE (77% vs 36%, p = 0.05) but not the CE (42% vs 75%, p = 0.20). Overall, 1-year survival improved in the CE (90%) from the EE (63%) (p = 0.05), mainly due to increased survival for PVF (82 vs 38%, p = 0.04). Post-HT survival for failing Fontan patients has improved, particularly for PVF. In the CE, our Fontan patients had a 1-year post-HT survival similar to other indications.

Heterogenous haemodynamic effects of adaptive servoventilation therapy in sleeping patients with heart failure and Cheyne-Stokes respiration compared to healthy volunteers.

This study investigated the haemodynamic effects of adaptive servoventilation (ASV) in heart failure (HF) patients with Cheyne-Stokes respiration (CSR) versus healthy controls. Twenty-seven HF patients with CSR and 15 volunteers were ventilated for 1h using a new ASV device (PaceWave™). Haemodynamics were continuously and non-invasively recorded at baseline, during ASV and after ventilation. Prior to the actual study, a small validation study was performed to validate non-invasive measurement of Stroke volume index (SVI). Non-invasive measurement of SVI showed a marginal overall difference of -0.03±0.41 L/min/m(2) compared to the current gold standard (Thermodilution-based measurement). Stroke volume index (SVI) increased during ASV in HF patients (29.7±5 to 30.4±6 to 28.7±5mL/m(2), p<0.05) and decreased slightly in volunteers (50.7±12 to 48.6±11 to 47.9±12mL/m(2)). Simultaneously, 1h of ASV was associated with a trend towards an increase in parasympathetic nervous activity (PNA) in HF patients and a trend towards an increase in sympathetic nervous activity (SNA) in healthy volunteers. Blood pressure (BP) and total peripheral resistance response increased significantly in both groups, despite marked inter-individual variation. Effects were independent of vigilance. Predictors of increased SVI during ASV in HF patients included preserved right ventricular function, normal resting BP, non-ischaemic HF aetiology, mitral regurgitation and increased left ventricular filling pressures. This study confirms favourable haemodynamic effects of ASV in HF patients with CSR presenting with mitral regurgitation and/or increased left ventricular filling pressures, but also identified a number of new predictors. This might be mediated by a shift towards more parasympathetic nervous activity in those patients.

(75) - Improved Transplant Survival in Failed Fontan Patients With Preserved Ventricular Function in the Current Era

Previous reports suggest Fontan patients with impaired ventricular function (IVF) have superior heart transplant (HT) outcomes compared to those with preserved ventricular function (PVF) and failed Fontan physiology. PVF patients have more primary graft failure (GF) and higher aortopulmonary collateral (APC) burden. We evaluated our management to reduce volume load pre-HT in Fontan patients in the current era.

Predicting reintubation, prolonged mechanical ventilation and death in post-coronary artery bypass graft surgery: a comparison between artificial neural networks and logistic regression models.

IntroductionIn coronary artery bypass (CABG) surgery, the common complications are the need for reintubation, prolonged mechanical ventilation (PMV) and death. Thus, a reliable model for the prognostic evaluation of those particular outcomes is a worthwhile pursuit. The existence of such a system would lead to better resource planning, cost reductions and an increased ability to guide preventive strategies. The aim of this study was to compare different methods – logistic regression (LR) and artificial neural networks (ANNs) – in accomplishing this goal.Material and methodsSubjects undergoing CABG (n = 1315) were divided into training (n = 1053) and validation (n = 262) groups. The set of independent variables consisted of age, gender, weight, height, body mass index, diabetes, creatinine level, cardiopulmonary bypass, presence of preserved ventricular function, moderate and severe ventricular dysfunction and total number of grafts. The PMV was also an input for the prediction of death. The ability of ANN to discriminate outcomes was assessed using receiver-operating characteristic (ROC) analysis and the results were compared using a multivariate LR.ResultsThe ROC curve areas for LR and ANN models, respectively, were: for reintubation 0.62 (CI: 0.50–0.75) and 0.65 (CI: 0.53–0.77); for PMV 0.67 (CI: 0.57–0.78) and 0.72 (CI: 0.64–0.81); and for death 0.86 (CI: 0.79–0.93) and 0.85 (CI: 0.80–0.91). No differences were observed between models.ConclusionsThe ANN has similar discriminating power in predicting reintubation, PMV and death outcomes. Thus, both models may be applicable as a predictor for these outcomes in subjects undergoing CABG.

Emerging hemodynamic signatures of the right heart (Third International Right Heart Failure Summit, part 2).

Despite the importance of preserved right ventricular structure and function with respect to outcome across the spectrum of lung, cardiac, and pulmonary vascular diseases, only recently have organized efforts developed to consider the pulmonary vascular-right ventricular apparatus as a specific unit within the larger context of cardiopulmonary pathophysiology. The Third International Right Heart Failure Summit (Boston, MA) was a multidisciplinary event dedicated to promoting a dialogue about the scientific and clinical basis of right heart disease. The current review provides a synopsis of key discussions presented during the section of the summit titled "Emerging Hemodynamic Signatures of the Right Heart." Specifically, topics emphasized in this element of the symposium included (1) the effects of pulmonary vascular dysfunction at rest or provoked by exercise on the right ventricular pressure-volume relationship, (2) the role of pressure-volume loop analysis as a method to characterize right ventricular inefficiency and predict right heart failure, and (3) the importance of a systems biology approach to identifying novel factors that contribute to pathophenotypes associated with pulmonary arterial hypertension and/or right ventricular dysfunction. Collectively, these concepts frame a forward-thinking paradigm shift in the approach to right heart disease by emphasizing factors that regulate the transition from adaptive to maladaptive right ventricular-pulmonary vascular (patho)physiology.

Abstract 19288: Pulmonary Hypertension and Sex Hormone Depletion Affect Lung and Right Ventricular Estrogen Receptor Expression

Introduction: Women with pulmonary arterial hypertension exhibit more preserved right ventricular (RV) function than men. The underlying mechanisms are unknown. We measured 17beta-estradiol (E2) levels and lung and RV expression of the two main estrogen receptors (ERalpha and -beta) in male and in intact or ovariectomized (OVX) female rats with Su5416/hypoxia (SuHx)-induced pulmonary hypertension (PH). Hypothesis: E2 is required for adaptation to increased RV afterload in females, and ER expression is inversely correlated with PH severity. Methods: Male and age-matched female Sprague-Dawley rats received Su5416 (20mg/kg), followed by 3 weeks of hypoxia (Patm=362 mmHg) and 4 weeks of room air. Selected females underwent OVX with or without concomitant E2 repletion (75 mcg/kg/d). RV hypertrophy (RV/[LV+S]), RV systolic pressure (RVSP), and PA muscularization were measured; complemented by echocardiographic assessment of RV function and measurement of exercise capacity (VO2max). In addition, we assessed RV pro-apoptotic signaling (bcl-2/bax; caspase-3 activity), serum E2 levels, and lung and RV ER expression by Western blot. N was 7-8/group. P&lt;0.05 was considered significant. Results: While no sex differences were noted in RV/(LV+S), RVSP or PA remodeling, female SuHx rats exhibited more preserved cardiac indices (CI; p&lt;0.05). OVX worsened SuHx-induced alterations in RV hypertrophy, RVSP and CI (p&lt;0.05). In turn, E2 replacement in SuHx-OVX rats prevented SuHx-induced alterations in PH endpoints and RV function; this was accompanied by attenuated RV pro-apoptotic signaling. RV ERbeta decreased in OVX SuHx females, but was restored with E2 repletion (p&lt;0.05). RV ERbeta correlated negatively with RVSP and RV/(LV+S), and positively with RV bcl-2/bax (p&lt;0.05). Similarly, serum E2 levels correlated negatively with RVSP and RV/(LV+S) (p&lt;0.05). While healthy females exhibited higher lung ERbeta than healthy males (p&lt;0.05), no such differences were observed in SuHx-PH. Neither lung nor RV ERalpha was affected by PH or hormone depletion. Conclusions: E2 is required for female adaption to SuHx-PH, through a mechanism that may involve ERbeta-mediated RV cell viability signaling, thus allowing for better adaptation to increases in RV afterload.

A Mock Circulatory System to Assess the Performance of Continuous-Flow Left Ventricular Assist Devices (LVADs)

Hemodynamic performances comparisons between different types of left ventricular assist devices (LVADs) remain difficult in a clinical context. The aim of this study was to create an experimental model to assess and compare two types of LVAD under hemodynamic conditions that simulated physical effort and pulmonary hypertension. An experimental mock circulatory system was created to simulate the systemic and pulmonary circulations and consisted of pulsatile left and right cardiac simulators (cardiowest pump), air/water tanks to model compliances, and tubes to model the venous and arterial resistances. Two types of continuous-flow ventricular assist devices were connected to this pulsated model: an axial flow pump, Heartmate II (HTM II), and a centrifugal pump, VentrAssist (VTA). The hemodynamic conditions at rest and during exercise were replicated. Mean aortic pressures were not significantly different at rest and during effort but mean flow under maximum pump speed was higher with HTM II (13 L vs. 10 L, p = 0.02). Left atrial pressure was lower at rest and during effort for the HTM II (11 mm Hg vs. 3 mm Hg, p = 0.02 and 9 mm Hg vs. 2 mm Hg, p = 0.008) than with the VTA, but with greater risk of left-ventricle suck-down for the axial flow. Power consumption for a similar flow was lower with the VTA during rest (4.7 W vs. 6.9 W, p = 0.002) and during effort (4.3 W vs. 6.6 W, p = 0.008). In case of high pulmonary vascular resistance with preserved right ventricular function, lower right ventricular pressure was obtained with HTM II (21 mm Hg vs. 28 mm Hg, p = 0.03). Observed results are in favor of a better discharge of the left and right cavities with the HTM II compared to the VTA yet with a higher risk of left cavity collapse occurrence.

Beyond a Broken Heart: Circulatory Dysfunction in the Failing Fontan

The role of ventricular dysfunction in late morbidity and mortality of univentricular hearts has been described previously. However, a significant proportion of adult Fontan patients who die or require heart transplantation do so with preserved ventricular function. The clinical deterioration in patients who have undergone Fontan palliation requires a broader view of circulatory dysfunction, one that takes into account the complex interaction of regulatory systems affecting hepatic, renal, and pulmonary blood flow, in addition to cardiac function. This review focuses primarily on the pathophysiology of multiple organ involvement in this circulatory dysfunction, with particular focus on the consequences of hepatic dysfunction and portal hypertension. The authors discuss hepatic perfusion, both in health and disease, and review the current understanding of liver histopathology and liver disease in adult Fontan patients and similar clinicopathologic states. They compare and contrast features of postsinusoidal portal hypertension with more typical adult cirrhotic disease. Finally, they delineate the related effects of portal hypertensive physiology on the systemic and pulmonary vasculature, the kidney, and the heart itself and discuss how these changes affect the care of the adult Fontan patient.

Pacing therapy in children.

The importance of ventricular pacing site in pediatric pacemaker therapy has gradually become recognized. We reviewed our experience with a left ventricular (LV)-prioritized pacing strategy. METHODS AND RESULTS: Between 2000 and 2012, 60 patients underwent 76 permanent pacemaker implantations. Eight of the 29 reoperations involved ventricular lead repositioning for pacing-induced ventricular dysfunction. Freedom from ventricular lead failure was 96.3%, 86.8%, and 81.0% at 1, 3, and 5 years, respectively. The independent predictors of ventricular lead failure were age (P=0.026) and peak minimal energy threshold within 6 months (P=0.035). At the measured points, redo bipolar, steroid-eluting leads had significantly better pacing properties than did redo non-steroid-eluting, screw-in leads (P=0.0009-0.03). Ventricular lead repositioning was effective in the 5 patients with systemic LV pacing, whereas its efficacy was inconsistent in patients with single-ventricle or systemic right ventricular (RV) pacing. At a median follow-up of 59 months, the 28 patients with LV pacing had preserved ventricular function (LV fraction shortening, 0.34±0.09). The outcome of this LV-prioritized pacing strategy in pediatric patients was excellent, demonstrating preserved ventricular function. Bipolar, steroid-eluting, epicardial pacing leads achieved good pacing properties, even in reoperation patients. In children with systemic LV and RV pacing-induced ventricular dysfunction, a conversion to LV apex pacing was an attractive alternative to cardiac resynchronization therapy.

No association between scar size and characteristics on T-wave Alternans in post-myocardial infarction patients with relatively preserved ventricular function presented with nonsustained ventricular tachycardia.

Microvolt T-wave Alternans (TWA) is associated with abnormal repolarization and predicts arrhythmic mortality in patients with previous myocardial infarction (MI). Infarct tissue size and heterogeneity characterized by cardiac magnetic resonance (CMR) has been shown to be associated with arrhythmogenic substrates and sudden cardiac death. Although both delayed enhancement-CMR (de-CMR) and TWA are useful in risk stratification of post-MI patients with preserved left ventricular function, the relationship between scar size and TWA has not studied yet. In this study, we aimed to study the relation between TWA and scar size and characteristics assessed with CMR in post-MI patients (pts) with relatively preserved systolic function presented with nonsustained VT. This observational cross-sectional study was enrolled 36 post-MI patients with mild-systolic dysfunction and non-sustained ventricular tachycardia. Eight pts were excluded. Both TWA and contrast enhanced CMR were performed. Left ventricular ejection fraction (LVEF), dense scar, peri-infarct zone and total scar masses were assessed and these values to left ventricular (LV) mass ratios were calculated. Infarct ratios and characteristics were determined and compared among patients with negative TWA and those with positive TWA. For the positive (n=12) vs. negative (n=16) TWA patients there were no significant difference between LVEF (44.9 ± 5.4% vs. 44.0 ± 3.2%, p=NS) and LV masses (121.89 ± 26.56 g vs. 106.14 ± 21.16 g, p=NS). The ratio of scar core to LV mass (3.37 ± 0.68% vs. 3.31 ± 1.01%, p=NS), peri-infarct zone to LV mass (23.61 ± 7.93% vs. 21.64 ± 9.08%, p=NS), total scar to LV mass (26.98 ± 7.86% vs. 24.96 ± 9.62%, p=NS) were all similar. There were no association between scar size and infarct heterogeneity and prevelance of TWA in post-MI patients with relatively preserved LVEF with non-sustained VT. Our data suggest that these two modalities may reflect different arrhythmogenic mechanisms in this cohort.