Fatima I. Lunze

Cardiac allograft function during the first year after transplantation in rejection-free children and young adults.

Background—Allograft dysfunction is a common finding early after heart transplant (HT). We sought to assess the recovery of left (LV) and right ventricular (RV) function during the first year after HT in children and young adults using pulsed-wave tissue Doppler imaging. Methods and Results—We analyzed serially performed echocardiography in 44 pediatric HT recipients (median age: 7.3 years at HT) who remained rejection-free during the first year post-transplant. Age-based normative values for systolic (S′), early-diastolic (E′), and late-diastolic (A′) velocities obtained using pulsed-wave tissue Doppler imaging in 380 healthy children were used to transform patient data into z scores. Pulsed-wave tissue Doppler imaging studies ⩽10 days post-HT demonstrated biventricular systolic and diastolic dysfunction with most prominent impairment in RV systolic function (S′ z score −2.7±0.8), RV early-diastolic filling (E′ z score −2.3±1.1), and LV early-diastolic filling (E′ z score −2.3±1.1). LV systolic function (S′ z score) and late-diastolic filling (A′ z score) improved to normal in 11 to 30 days, LV early-diastolic filling (E′ z score) in 4 to 6 months, and RV early-diastolic filling in 6 to 9 months (P<0.001 for all on longitudinal analysis). However, RV systolic function (RV S′ z score −1.2±1.1) remained impaired 1-year post-transplant. Analysis of serial cardiac catheterization studies showed that RV and LV filling pressures were elevated early post-HT and declined gradually during the first year post-transplant. Conclusions—Pediatric HT recipients have biventricular dysfunction using pulsed-wave tissue Doppler imaging early after HT with most significant impairment in RV systolic function and RV and LV early-diastolic filling. Although other aspects of LV and RV function normalize in 6 to 9 months, RV systolic function remains abnormal 1 year-post-transplant.

Effects of Transcatheter Pulmonary Valve Replacement on the Hemodynamic and Ventricular Response to Exercise in Patients With Obstructed Right Ventricle-to-Pulmonary Artery Conduits

OBJECTIVES This study sought to investigate the effects of exercise on the right ventricle in patients with an obstructed right ventricular outflow tract (RVOT) conduit before and after transcatheter pulmonary valve replacement (TPVR). BACKGROUND Conventionally, assessment of the right ventricle in congenital heart disease patients with dysfunctional RVOT conduits is performed at rest. However, this does not reflect dynamic exercise changes. METHODS Exercise stress echocardiography (ESE) before and 6 months after TPVR was performed. ESE protocol included measurement of rest and immediate post-exercise RVOT maximal instantaneous gradients (MIGs), right ventricular (RV) systolic pressure, 2-dimensional fractional area change, and global longitudinal strain (GLS). RESULTS Twenty patients with RVOT conduit obstruction (median age, 18 years), the majority (n = 14) with tetralogy of Fallot, completed the study. Pre-TPVR, the median resting MIG across the RVOT was 53 mm Hg (23 to 95 mm Hg) and increased to 93 mm Hg (49 to 156 mm Hg; p < 0.001) with exercise. After TPVR, the median MIG at rest was 26 mm Hg (6 to 41 mm Hg, and after exercise, it was 45 mm Hg (9 to 102 mm Hg), both significantly lower than before TPVR (p ≤ 0.001), but there was still a substantial increase in gradient with exercise in many patients. The RV fractional area change, RV GLS, and left ventricular GLS, both at rest and after exercise, were significantly greater after TPVR than before. A greater pre-TPVR exercise-related increase in RV function was associated with improvement in peak Vo2 after TPVR (p = 0.01). CONCLUSIONS In patients with obstructed RVOT conduits, TPVR resulted in significant improvement in conduit stenosis and RV function at both rest and at peak exercise and in exercise cardiopulmonary function. The ability to augment RV function at peak exercise before TPVR was associated with improved exercise capacity 6 months after TPVR.

Utility of exercise stress echocardiography in pediatric cardiac transplant recipients: A single-center experience

BACKGROUND Annual coronary angiography (ANG) to assess for significant epicardial coronary artery disease (CAD) is an integral part of follow-up care for pediatric cardiac transplant recipients at Childrens Hospital Boston. Exercise stress echocardiography (ESE) is an important, non-invasive tool for the detection of ischemia in adults but has been rarely used in children. Therefore, the aim of this study was to assess the feasibility and utility of ESE in excluding ANG-detected epicardial CAD at our center, where ESE has been implemented since 2007. METHODS We conducted a retrospective review of all pediatric cardiac transplant recipients at our institution who had undergone ESE and ANG between January 2007 and December 2010, and with testing performed < 12 months apart. ESE results were compared against ANG. RESULTS The study cohort comprised 47 cardiac transplant recipients. One patients ESE images were inadequate for interpretation. Of the remaining 46 patients, ESE had a sensitivity of 88.9% (95% confidence limits [CL], 51.8%, 99.7%), a specificity of 91.9% (95% CL, 71.8%, 98.3%), and a negative predictive value of 97% (95% CL, 85.1%, 99.1%) for the ANG-detected CAD. CONCLUSIONS This large, single-center study showed ESE was feasible and had a high specificity and excellent negative predictive value in excluding epicardial CAD in pediatric cardiac transplant recipients. Future prospective, large-scale studies are needed to confirm these findings and help identify a subset of children for whom a negative ESE could decrease the frequency of routine ANG.

Preserved regional atrial contractile function following extra-atrial rather than intra-atrial type Fontan operation : A tissue Doppler imaging study

SummaryObjectiveTo determine the univentricular and atrial function in patients following Fontan operation using tissue Doppler echocardiography (TDE).SettingHospital-based outpatient clinic and inpatient unit.PatientsThirty-six patients (mean age 13 ys [2–34 ys]) after Fontan procedure and 30 healthy individuals matched for age and heart rate.Main outcome measuresPulsed wave Doppler derived Tei index was determined for global univentricular function. Tissue-Doppler derived strain rate and strain were measured for regional ventricular function. Different planimetric approaches were used to evaluate the global atrial function. Strain rate was measured for regional atrial contractile function.ResultsThe Tei index, reflecting global univentricular function, was significantly higher in Fontan patients than in the control group (p<0.001). The regional ventricular contractile function, which was determined by TDE derived strain and strain rate, was significantly lower in Fontan patients than in healthy controls (p<0.001). The global atrial function evaluated planimetrically, and the regional atrial function assessed using the TDE strain rate, were significantly lower in Fontan patients than in normal controls (p<0.001, p<0.001, respectively). A comparison of different types of Fontan operations with extra-atrial or intra-atrial baffle showed a better regional left atrial wall strain rate in patients with extra-atrial baffle than with intra-atrial baffle.ConclusionPatients who have undergone the Fontan procedure may present with altered ventricular and atrial performance independent of whether the extra-atrial or intraatrial type Fontan operation was performed. However, the regional atrial contractile function seems to be better preserved following the extra-atrial type Fontan operation.

Exercise Stress Echocardiographic Assessment of Outflow Tract and Ventricular Function in Patients With an Obstructed Right Ventricular-to-Pulmonary Artery Conduit After Repair of Conotruncal Heart Defects

This study assessed right ventricular (RV) and RV outflow tract (RVOT) function and pressure in response to exercise in patients with an obstructed RV-pulmonary artery (PA) conduit using exercise stress echocardiography (ESE) to evaluate these parameters. RV-PA conduits inevitably develop stenosis and/or regurgitation over time. Assessment of conduit obstruction only at rest may not reveal the extent of physiologic perturbation related to RV pressure loading. Patients with a stenotic RV-PA conduit who were being considered for transcatheter pulmonary valve placement were approached prospectively. ESE was performed and ventricular images were obtained at rest and at peak exercise. Forty patients (median age 17 years) were enrolled. Most patients had tetralogy of Fallot (63%) and were in New York Heart Association class II (59%). Exercise stress echocardiographic images were adequate in 38 patients (95%). With exercise there was a significant increase in maximum instantaneous RVOT gradient from rest (59 vs 96 mm Hg, p <0.001); exercise-induced change in RVOT gradient correlated with global RV strain at rest (r = -0.3, p = 0.05). Compared to measurements at rest there were significant increases in median peak longitudinal strain of the left ventricular free wall, interventricular septum, and global left ventricular strain at peak exercise. There were no significant changes in median RV strain at peak exercise (RV free wall -14.3 [-26, -8] at rest vs -15.2 [-27, -3] at peak exercise, p = 0.87; global RV strain -13.9 [-32, -9] vs -15.1 [-23, -6], p = 0.11). In conclusion, using ESE it was possible to evaluate abnormal ventricular function and conduit dysfunction at peak exercise in patients with an obstructed RV-PA conduit.

Heterogeneity of Regional Function and Relation to Ventricular Morphology in Patients With Fontan Circulation

The relation between underlying ventricular morphology and regional function in patients with Fontan circulation remains unclear. The aim of this study was to compare regional function and its heterogeneity in patients with tricuspid atresia (TA), biventricular apex-forming morphology (BiV), and controls. Nineteen patients (median age 12 years) with Fontan circulation who presented consecutively were prospectively enrolled and compared with age- and heart rate-matched controls. Most patients were in New York Heart Association class I (63%). Longitudinal systolic strain (S), systolic strain rate (SRsys), and early diastolic strain rate (SRdia) peaks were obtained from 6 ventricular segments, and a coefficient of variation by segment was calculated as a measure of regional heterogeneity. Systolic S, SRsys and SRdia peaks were decreased at the right and left lateral walls in both patient groups compared with controls (p ≤0.001 for all). Patients with TA had higher systolic S and SRsys in the middle of the right lateral wall than those with BiV morphology (p = 0.009 and p = 0.001, respectively). The mean coefficients of variation assessed by S and SRsys were similar in controls and patients with TA but lower in those with BiV than in controls and patients with TA (p <0.001 and p = 0.01, respectively). The mean coefficient of variation assessed by SRdia was greater only in patients with BiV than in controls (p = 0.001). In conclusion, patients with Fontan circulation have more heterogeneous systolic and early diastolic regional function than healthy control subjects, and patients with TA have better systolic regional function in the middle of the right lateral wall and less systolic heterogeneity than patients with BiV morphology.

Sexual violence from police and HIV risk behaviours among HIV-positive women who inject drugs in St. Petersburg, Russia - a mixed methods study

Police violence against people who inject drugs (PWID) is common in Russia and associated with HIV risk behaviours. Sexual violence from police against women who use drugs has been reported anecdotally in Russia. This mixed‐methods study aimed to evaluate sexual violence from police against women who inject drugs via quantitative assessment of its prevalence and HIV risk correlates, and through qualitative interviews with police, substance users and their providers in St. Petersburg, Russia.

Stigma and Human Rights Abuses against People Who Inject Drugs in Russia—A Qualitative Investigation to Inform Policy and Public Health Strategies

Introduction Drug policing practices in the Russian Federation (Russia) are often punitive and have been shown to be associated with HIV risk behaviors among people who inject drugs (PWID). Less is known about strategies to address the problem in that setting, where substance use stigma is highly persistent. A better understanding of forms, causes and consequences of drug policing in Russia could inform drug policy in a context of substantial policy resistance. This qualitative study’s goal is to characterize the phenomenon of police involvement with Russian PWID and to explore strategies for drug policing in the Russian country context. Methods Using a semi-structured interview guide, we collected data from a purposive sample of 23 key informants including PWID, police officers, and experts from civil society and international organizations in Russia. We used a thematic analysis approach to inductively generate new insight into the phenomenon of police involvement and potential strategies to address it. Results Policing practices involving PWID include unjustified arrests, planting of false evidence and extrajudicial syringe confiscations, and often constitute human rights violations. Russian PWID personally experienced police violence as ubiquitous, taking on various forms such as beating, unjustified arrests, verbal harassment, and coercion. The persistent societal stigma dehumanizes PWID, and such stigmatization facilitates police abuse. To address stigma and overcome the PWID-police adversity, study participants suggested fostering a mutual understanding between the police and public health sectors. Conclusions Participants describe substantial human rights violations as part of policing illicit drug use in Russia. Police should include principles of effective prevention of substance use and HIV risk reduction in their trainings. Alignment of public safety and public health goals could address drug use-related risks and HIV prevention among key populations in Russia.

Addressing the burden of post-conflict surgical disease - strategies from the North Caucasus.

The 2004 terror attack on a school in Beslan, North Caucasus, with more than 1300 children and their families taken hostage and 334 people killed, ended after extreme violence. Following the disaster, many survivors with blast ear injuries developed complications because no microsurgery services were available in the region. Here, we present our strategies in North Ossetia to strengthen subspecialty surgical care in a region of instable security conditions. Disaster modifies disease burden in an environment of conflict-related health-care limitations. We built on available secondary care and partnered international with local stakeholders to reach and treat victims of a humanitarian disaster. A strategy of mutual commitment resulted in treatment of all consenting Beslan victims with blast trauma sequelae and of non disaster-related patients. Credible, sustained partnerships and needs assessments beyond the immediate phases after a disaster are essential to facilitate a meaningful transition from humanitarian aid to capacity building exceeding existing insufficient standards. Psychosocial impacts of disaster might constitute a barrier to care and need to be assessed when responding to the burden of surgical disease in conflict or post-conflict settings. Involving local citizen groups in the planning process can be useful to identify and access vulnerable populations. Integration of our strategy into broader efforts might strengthen the local health system through management and leadership.

Feasibility of exercise stress echocardiography and myocardial response in patients with repaired congenital heart disease

Background Exercise stress echocardiography (ESE) can unmask ventricular dysfunction in asymptomatic patients with congenital heart disease (CHD), but its acquisition and interpretation is often challenging, and the method has not been validated in CHD. This study aimed to evaluate the feasibility of ESE using Doppler imaging and to assess myocardial response to exercise in patients with biventricular (BiV) and univentricular (UniV) circulation after CHD repair. Methods In this single‐center prospective study, we recruited 55 participants (17 females), median age 14 years (8‐22 years). Our analysis categorized participants in these three groups: with structurally normal hearts as controls (n = 21), with BiV circulation (n = 20) and with UniV circulation (n = 14). We acquired ESE images of the systemic ventricle including pulsed‐wave flow and spectral tissue Doppler imaging (TDI) of lateral free wall before and immediately after standard, symptom‐limited exercise tests on an electronically braked cycle ergometer. Results During ESE we obtained inflow E‐wave and TDI systolic (S′) and early diastolic (E′) velocities in 93% to 100% of participants at rest and in 90% to 100% of participants post exercise. Feasibility to obtain Doppler imaging parameter was the same across study groups. The myocardial response to exercise was increase in heart rate (HR), S′ and inflow E‐wave velocity in all participants. Patients with BiV circulation had preserved ventricular function at rest. While patients with UniV circulation had low S′, E′, and E‐wave velocities at rest in comparison to controls and to BiV group (all P < .001), both patients with BiV and UniV circulation showed significant increases in HR, S′ velocity and inflow E‐wave velocity post exercise, with magnitudes of these increases higher in controls than in the BiV and UniV group. The S′ and E′ velocities were strongly associated with lower percent predicted peak oxygen consumption VO2 (rs = 0.614 and rs = 0.64, respectively, both P < .001). Conclusion ESE with Doppler imaging is a practical noninvasive diagnostic method and sufficiently robust for the assessment of morphologic LV/systemic ventricles under exercise in patients after biventricular and univentricular CHD repair. Although patients with BiV and UniV circulation had both preserved myocardial response to exercise, the magnitude of this response was the lowest in patients with UniV circulation.