Transcatheter occlusion of venovenous collaterals in the total cavopulmonary Fontan circulation.

BACKGROUND: Venovenous collaterals are abnormal connections between the systemic and pulmonary venous systems. They are commonly seen in the Fontan circulation and may lead to significant hypoxaemia. Transcatheter closure of venovenous collaterals is a potential but controversial treatment as the long-term benefits and outcomes are not well understood. METHODS: This retrospective cohort study utilised data from the Australian and New Zealand Fontan Registry. Patients who underwent transcatheter venovenous collateral occlusion for hypoxemia from the year 2000 onwards were included. Atriopulmonary and Kawashima-type Fontan circulations were excluded to reflect a more contemporary Fontan cohort. RESULTS: Nineteen patients (age 19.3 ± 7.8 years, 53% female) underwent transcatheter venovenous collateral occlusion. Compared to baseline, mean oxygen saturation was improved at latest follow-up (90.5% vs 87.0%; p = 0.003). Nine patients achieved a clinically significant response (defined as an increase of at least 5% to 90% or greater), and this was associated with lower baseline Fontan pressures (12.9 v 15.6 mmHg; p = 0.02). No heart failure hospitalisations, arrhythmia, transplant referrals, or mortality were observed during the median follow-up period of 4 years. Two patients experienced thromboembolic events and five patients underwent re-intervention. CONCLUSION: Transcatheter occlusion of venovenous collaterals in Fontan patients with chronic hypoxaemia resulted in a modest increase in oxygenation over a median follow-up of 4 years and longer-term prognosis did not appear to be adversely affected. Lower Fontan pressures at baseline were associated with a greater improvement in oxygenation.

A case series describing the multidisciplinary management of pulmonary arterial hypertension in pregnancy: Time for optimism.

BACKGROUND: Pulmonary arterial hypertension (PAH) is a high-risk condition during pregnancy, with recent literature describing mortality rates of up to 23%. AIM: To describe the course and outcomes of pregnancy for women with PAH in a major Australian metropolitan referral centre over a 15-year period. METHODS: Retrospective review of medical records of all pregnant women with PAH over the period 2005-2020. RESULTS: We report the outcomes of nine pregnancies in six women. In five women, seven pregnancies proceeded to term with birth of a healthy neonate, five vaginal births and two caesareans. Two women opted for a termination of pregnancy in the first trimester following counselling. The planning of care and patient-centred decision-making was individually tailored by a multidisciplinary team. The pulmonary hypertension clinic provided specialist support including the management of pulmonary vasodilators. All women who delivered a live offspring received neuraxial anaesthesia. CONCLUSIONS: Women with this condition are ideally managed in a centre with expertise in PAH; counselling regarding the risks is imperative. Regional anaesthesia, irrespective of the mode of delivery, facilitated safe delivery and improved patient experience. The option of aiming for a term vaginal birth needs to be considered in these complex women.

Melody valve insertion for relief of "Tricuspid" stenosis in an unbalanced atrioventricular septal defect.

A Melody valve was successfully placed across a very stenotic right-sided component of a common atrioventricular valve because of ongoing troublesome arrhythmias in a young woman with an unbalanced atrioventricular septal defect, a very dilated right atrium and a hypoplastic right ventricle. Four years later, she remains well.

Ten Years of Percutaneous Pulmonary Valve Implantation in Australia and New Zealand.

OBJECTIVE: This study sought to investigate the characteristics, morbidity (including the rate of infective endocarditis and valve replacement) and mortality of individuals undergoing percutaneous pulmonary valve implantation in Australia and New Zealand since the procedure has been performed. BACKGROUND: The outcomes of percutaneous pulmonary valve implantation in Australia and New Zealand have not been evaluated. Recent international data, including patients from New Zealand, suggests the rate of infective endocarditis is not insignificant. METHODS: A retrospective multi-site cohort study was undertaken via medical record review at the centres where percutaneous pulmonary valve implantation has been performed. All procedures performed from 2009-March 2018 were included. Individuals were identified from local institution databases. Data was collected and analysed including demographics, details at the time of intervention, haemodynamic outcome, post procedure morbidity and mortality. Multi-site ethics approval was obtained. RESULTS: One hundred and seventy-nine (179) patients attended the cardiac catheter laboratory for planned percutaneous pulmonary valve implantation. Of these patients, 172 underwent successful implantation. Tetralogy of Fallot and pulmonary atresia were the most common diagnoses. The median age at procedure was 19 years (range 3-60 yrs). There was a significant improvement in the acute haemodynamics in patients undergoing percutaneous pulmonary valve implantation for stenosis. Seven (7) patients (3.9%) experienced a major procedural/early post procedure complication (death, conversion to open procedure, cardiac arrest), including two deaths. The annualised rates of infective endocarditis and valve replacement were 4.6% and 3.8% respectively. There was one death related to infective endocarditis in follow-up. CONCLUSIONS: Percutaneous pulmonary valve replacement is a relatively safe method of rehabilitating the right ventricular outflow tract.

Management errors in adults with congenital heart disease: prevalence, sources, and consequences.

Aims: Improved survival has resulted in increasing numbers and complexity of adults with congenital heart disease (ACHD). International guidelines recommend specialized care but many patients are still not managed at dedicated ACHD centres. This study analysed referral sources and appropriateness of management for patients referred to our tertiary ACHD Centre over the past 3 years. Methods and results: We compared differences in care between patients referred from paediatric/ACHD-trained vs. general adult cardiologists, according to Adherence (A) or Non-Adherence (NA) with published guidelines. Non-Adherent cases were graded according to the severity of adverse outcome or risk of adverse outcome. Of 309 consecutively referred patients (28 ± 14 years, 51% male), 134 (43%) were from general cardiologists (19% highly complex CHD) and 115 (37%) were from paediatric cardiology or ACHD specialists (33% highly complex CHD). Sixty referrals (20%) were from other medical teams and of those, 31 had been lost to follow-up. Guideline deviations were more common in referrals from general compared to CHD-trained cardiologists (P < 0.001). Of general cardiology referrals, 49 (37%) were NA; 18 had catastrophic or major complications (n = 2, 16 respectively). In contrast, only 12 (10%) of the paediatric/ACHD referrals were NA, but none of these were catastrophic and only 3 were major. Simple, moderate, and highly complex CHD patients were at increased risk of adverse outcome when not under specialized CHD cardiology care (P = 0.04, 0.009, and 0.002, respectively). Conclusion: Non-adherence with guidelines was common in the ACHD population, and this frequently resulted in important adverse clinical consequences. These problems were more likely in patients who had not been receiving specialized CHD care. Configuring healthcare systems to optimize 'whole of life' care for this growing population is essential.

Adult Congenital Heart Disease in Australia and New Zealand: A Call for Optimal Care.

BACKGROUND: Adult congenital heart disease (ACHD) is a relatively new subspecialty in the cardiology field. The prevalence of ACHD is estimated at ∼ 3,000 per million adult population. The ACHD patient group is estimated to grow at ∼ 5% per year and in the next decade it is forecast that 1 in 150 young adults will carry some form of ACHD diagnosis. These estimates translate to ∼ 72,000 ACHD patients in Australia and ∼ 14,000 in New Zealand, although no current numbers are available. The Cardiac Society of Australia and New Zealand (CSANZ) has recently published Recommendations for Standards of Care for Adult Congenital Heart Disease (ACHD) in 2016. There is currently no long-term plan or proposal to address this huge health care burden within the federal government. This document details the size of the problem insofar as it is known and recommends solutions to be implemented. METHODS: This document was developed by the Adult Congenital Heart Disease Working Group of the Paediatric and Congenital Council (the Congenital Heart Alliance of Australia and New Zealand) as a response to the chronic under resourcing in this area, the risk this poses to patients and clinicians, and the clear need for long-term planning to develop safe care pathways. RESULTS: These issues were raised with the CSANZ Board in December 2015 and the document was developed in response to the Board's request for more information. The current iteration was finalised on 14 November 2017. CONCLUSIONS: The authorship group comprised participants in the CSANZ adult CHD standards of care recommendations from 2013 with the inclusion of some newly trained ACHD cardiologists, who represented most states and territories across ANZ. None of the authors has any academic or professional conflict of interest.

Right Ventricular Mass is Associated with Exercise Capacity in Adults with Repaired Tetralogy of Fallot.

The relationship between exercise capacity and right ventricular (RV) structure and function in adult repaired tetralogy of Fallot (TOF) is poorly understood. We therefore aimed to examine the relationships between cardiac MRI and cardiopulmonary exercise test variables in adult repaired TOF patients. In particular, we sought to determine the role of RV mass in determining exercise capacity. Eighty-two adult repaired TOF patients (age at evaluation 26 ± 10 years; mean age at repair 2.5 ± 2.8 years; 23.3 ± 7.9 years since repair; 53 males) (including nine patients with tetralogy-type pulmonary atresia with ventricular septal defect) were prospectively recruited to undergo cardiac MRI and cardiopulmonary exercise testing. As expected, these repaired TOF patients had RV dilatation (indexed RV end-diastolic volume: 153 ± 43.9 mL/m(2)), moderate-severe pulmonary regurgitation (pulmonary regurgitant fraction: 33 ± 14 %) and preserved left (LV ejection fraction: 59 ± 8 %) and RV systolic function (RV ejection fraction: 51 ± 7 %). Exercise capacity was near-normal (peak work: 88 ± 17 % predicted; peak oxygen consumption: 84 ± 17 % predicted). Peak work exhibited a significant positive correlation with RV mass in univariate analysis (r = 0.45, p < 0.001) and (independent of other cardiac MRI variables) in multivariate analyses. For each 10 g higher RV mass, peak work was 8 W higher. Peak work exhibits a significant positive correlation with RV mass, independent of other cardiac MRI variables. RV mass measured on cardiac MRI may provide a novel marker of clinical progress in adult patients with repaired TOF.

Detection of serious complications by MR imaging in asymptomatic young adults with repaired coarctation of the aorta.

BACKGROUND: Despite early repair, patients with aortic coarctation (CoA) continue to have a reduced life expectancy due to the development of late complications. We sought to define the rate of aortic abnormalities in patients with previous CoA repair, referred for surveillance magnetic resonance (MR) imaging. METHODS: We evaluated 59 asymptomatic adults consecutively for repaired CoA with MR imaging between 2008 and 2012. RESULTS: Patients were aged 29 ± 8 (16-49) years; 34 males (58%) and 34 with bicuspid aortic valve (58%). Median age at the time of initial repair was two years. Surveillance MR imaging was performed 23 ± 8 years post-procedure. The three most common interventions performed were subclavian-flap repair (25%), end-to-end repair (33%) and patch aortoplasty (33%). Re-intervention with balloon angioplasty or repeat surgery had been performed in 22% of subjects. There were 28 cases of recoarctation (48%), of which seven were at least moderate in severity. Repair site and ascending aortic aneurysm occurred in eight (14%) and four (7%) subjects, respectively. Freedom from any degree of recoarctation and other aortic complications was observed in eight subjects (14%). CONCLUSION: MR imaging detected a high rate of aortic abnormalities in asymptomatic adults after CoA repair, including 27% with clinically significant recoarctation and/or local aneurysm formation.

Right ventricular outflow tract enlargement prior to pulmonary valve replacement is associated with poorer structural and functional outcomes, in adults with repaired Tetralogy of Fallot.

BACKGROUND: Pulmonary valve replacement (PVR) is commonly performed late after Tetralogy of Fallot (TOF) repair. We examined the effects of PVR on cardiac structure, function and exercise capacity in adults with repaired TOF. METHODS: Eighteen adult patients with repaired TOF and severe pulmonary regurgitation (PR) with right ventricular (RV) dilatation requiring PVR for clinical reasons (age; 25±8 years) were recruited to undergo cardiac MRI (1.5T) and cardiopulmonary exercise testing before and 14±3 months after PVR. RESULTS: Reduced indexed RV end-diastolic volume (RVEDVi; 186±32mL/m(2) pre-op vs 114±20mL/m(2) post-op, p<0.001) was observed after PVR. "Normalisation" of RVEDVi (≤108mL/m(2)) was achieved in only seven of 18 patients. Pre-PVR RVEDVi correlated with post-operative change in RVEDVi (change=-72.1±20.4mL/m(2), r=-0.815, p<0.001). Exercise capacity remained high-normal post-PVR (% predicted maximal workload: 93±16% vs 91±12%, p=0.5). Regional RV volumes were assessed; RV outflow tract (RVOT) volumes were compared to the RV muscular corpus. Large pre-PVR RVOT volumes correlated negatively with post-surgical RV ejection fraction, peak VO2 and delta VO2 at anaerobic threshold (p<0.05 for all). CONCLUSIONS: Normalisation of RV volume is unlikely to be achieved above a pre-PVR RVEDVi of 165mL/m(2) or more. In particular, an enlarged RVOT prior to PVR predicts suboptimal structural and functional outcomes.

Management of Severe Coarctation of the Aorta and Bilateral Carotid Artery Stenosis: An Interventional Catch-22.

We present a case of an adult with concurrent severe aortic coarctation, bilateral carotid artery stenosis, and anomalous right subclavian artery, posing the interventional dilemma of accepting potential cerebral hyperperfusion syndrome vs hypoperfusion ischemic injury. Transcatheter stenting of the aortic coarctation was successfully performed without any neurological deficits. (Level of Difficulty: Beginner.).

Antioxidants protect from atherosclerosis by a heme oxygenase-1 pathway that is independent of free radical scavenging.

Oxidative stress is implicated in atherogenesis, yet most clinical trials with antioxidants, particularly vitamin E, have failed to protect against atherosclerotic diseases. A striking exception is probucol, which retards atherosclerosis in carotid arteries and restenosis of coronary arteries after angioplasty. Because probucol has in vitro cellular-protective effects independent of inhibiting lipid oxidation, we investigated the mode of action of probucol in vivo. We used three models of vascular disease: apolipoprotein E-deficient mice, a model of atherosclerosis; rabbit aortic balloon injury, a model of restenosis; and carotid injury in obese Zucker rats, a model of type 2 diabetes. Unexpectedly, we observed that the phenol moieties of probucol were insufficient, whereas its sulphur atoms were required for protection. Probucol and its sulphur-containing metabolite, but not a sulphur-free phenolic analogue, protected via cell-specific effects on inhibiting macrophage accumulation, stimulating reendothelialization, and inhibiting vascular smooth muscle cell proliferation. These processes were mediated via induction of heme oxygenase-1 (HO-1), an activity not shared by vitamin E. Our findings identify HO-1 as the molecular target of probucol. They indicate 2-electron rather than radical (1-electron) oxidants as important contributors to atherogenesis, and point to novel lead compounds for therapeutic intervention against atherosclerotic diseases.

Trastuzumab-induced cardiotoxicity: the role of two-dimensional myocardial strain imaging in diagnosis and management.

A 45-year-old female breast cancer patient developed heart failure during adjuvant trastuzumab therapy. Her initial left ventricular ejection fraction (LVEF) was 39% and corresponding global longitudinal and circumferential systolic strain measurements were also significantly reduced. Trastuzumab was ceased and supportive cardiac therapy commenced. The ensuing LVEF and systolic strain measurements showed consistent improvement so that trastuzumab was recommenced (while supportive cardiac therapy continued). At this point, reduced circumferential systolic strain with preserved LVEF was observed. Subsequent echocardiograms revealed further reductions in circumferential and longitudinal systolic strain without reductions in LVEF.

Platypnea-Orthodeoxia Syndrome in the Setting of Patent Foramen Ovale Without Pulmonary Hypertension or Major Lung Disease.

Background Patent foramen ovale (PFO)-associated platypnea-orthodeoxia syndrome is characterized by dyspnea and hypoxemia when upright. The pathogenesis is thought to involve an increase in right atrial pressure or change in degree of right to left shunting with upright posture. Methods and Results We sought to characterize patients with platypnea-orthodeoxia syndrome related to PFO without pulmonary hypertension. We retrospectively reviewed databases at 3 tertiary referral hospitals in New South Wales, Australia from 2000 to 2019. Fourteen patients with a mean age of 69±14 years had a PFO with wide tunnel separation. Mean New York Heart Association Classification was II (±0.9) and 7 inpatients had been confined to bed (from postural symptoms). Baseline oxygen saturations supine were 93%±5% and 84%±6% upright. Two patients had a minor congenital heart defect and 4 had mild parenchymal lung disease with preserved lung function. The mean aortic root diameter was 37±6 mm and distance between aortic root and posterior atrial wall was 16±2 mm. Platypnea-orthodeoxia syndrome was preceded by surgery in 5 patients and 1 patient had mild pneumonia. Successful closure of the PFO using an Amplatzer device was performed in 11 of 14 patients. Post-closure, all patients had New York Heart Association Classification I (improvement 1.6±0.9, P<0.003) and semi-recumbent oxygen saturations increased by 13%±8% (P<0.001, n=10). Conclusions Platypnea-orthodeoxia syndrome is a debilitating condition, curable by PFO closure. Anatomical distortion of the atrial septum related to a dilated aortic root or shortening of the distance between the aortic root and posterior atrial wall may contribute to the syndrome.

The role of intracoronary thrombolysis in selected patients presenting with ST-elevation myocardial infarction: a case series.

BACKGROUND: Primary percutaneous coronary intervention (PCI) is the cornerstone of management for ST-elevation myocardial infarction (STEMI). However, large intracoronary thrombus burden complicates up to 70% of STEMI cases. Adjunct therapies described to address intracoronary thrombus include manual and mechanical thrombectomy, use of distal protection device and intracoronary anti-thrombotic therapies. CASE SUMMARY: This series demonstrates the use of intracoronary thrombolysis in the setting of large coronary thrombus, bifurcation lesions with vessel size mismatch, diffuse thrombosis without underlying plaque rupture, and improving coronary flow to allow vessel wiring and proceeding to definitive revascularization. DISCUSSION: Larger intracoronary thrombus burden correlates with greater infarct size, distal embolization, and the associated no-reflow phenomena, and propagates stent thrombosis, with subsequent increase in mortality and major adverse cardiac events. Intracoronary thrombolysis may provide useful adjunct therapy in highly selected STEMI cases to reduce intracoronary thrombus and facilitate revascularization.

Coarctation of the aorta: evaluation and management.

PURPOSE OF REVIEW: Coarctation of the aorta is the discrete narrowing of the proximal descending aorta and is the sixth most common lesion in congenital heart disease. Repair of the coarctation can relieve the obstruction, but recurrent coarctation and future aneurysm formation can occur, and a heightened risk of vascular disease is present. This review focuses on advances in the management of native and previously treated coarctation and provides insights into future vascular risk. RECENT FINDINGS: Coarctation of the aorta is associated with other left heart obstructive lesions, and advances in the genetic basis of these conditions have been made. Recurrent coarctation and aneurysm formation are common after surgical and endovascular repair of coarctation of the aorta. Endovascular treatment is an acceptable alternative to surgical repair of native and recurrent coarctation. Covered stents and stent grafts can be used to treat arch complications with a low risk of complications. In spite of repair of the obstruction, hypertension persists and appears to be multifactorial due to a variety of factors, including endothelial dysfunction, aortic stiffness, altered arch morphology and increased ventricular stiffness. SUMMARY: People with previously repaired coarctation of the aorta require long-term surveillance for local complications with aortic imaging and surveillance and management of hypertension to prevent vascular disease.

Exercise capacity and biventricular function in adult patients with repaired tetralogy of Fallot.

BACKGROUND: Adult patients with repaired tetralogy of Fallot (rTOF) often have diminished exercise capacity. The primary objective of this study was to examine whether abnormalities of biventricular function play a role in exercise limitation in patients with rTOF. METHODS: This was a retrospective review of 99 adult patients with rTOF. Right ventricular (RV) and left ventricular (LV) function were assessed echocardiographically using the myocardial performance index (MPI). Maximal oxygen consumption (VO(2) Max) was measured during a level 1 cardiopulmonary exercise test. RESULTS: The mean age of the cohort was 34 +/- 11 years (50% females). Although most of the patients reported good functional capacity, the peak Vo(2)max was decreased at 22 +/- 6 mL/kg per minute (66% +/- 13% predicted Vo(2)max for age and sex). The mean RV and LV MPI were 0.30 +/- 0.07 and 0.42 +/- 0.09, respectively. In the multivariate model, higher RV MPI (P = .04) and LV MPI (P = .005) values, representing impaired ventricular function, were associated with diminished Vo(2)max. There was a significant correlation between the RV and LV MPI (r = 0.54, P = .001). CONCLUSIONS: Impairment of RV and LV function, as measured by MPI, is associated with diminished exercise capacity in patients with repaired tetralogy of Fallot. Furthermore, there is a linear relationship between the RV and LV function suggesting that ventricular interactions are contributing to the limited exercise capacity in this group of patients. Strategies aimed at preserving biventricular function or improving adverse ventricular interactions could help to improve functional capacity in these patients.

Coronary artery vasospasm in a patient with Churg-Strauss syndrome.

Patients with Churg-Strauss syndrome often suffer from unusual cardiac manifestations and sudden cardiac death. This differs from patients with other autoimmune disorders, who typically present with premature ischaemic heart disease. We report the case of a 56-year-old man with recurrent coronary vasospasm, including an inferoposterior ST-elevation myocardial infarction, complicated by bradycardic arrest. There was only minor coronary artery disease on coronary angiography. An elevated eosinophil count was noted. His medical history included allergic rhinitis with polyposis, adult-onset asthma and biopsy-proven eosinophilic oesophagitis. Review of his sinus biopsies demonstrated blood vessels with marked accumulation of eosinophils in extravascular areas. The patient, therefore, met the American College of Rheumatology criteria for Churg-Strauss syndrome. The patient was commenced on immunosuppression, with the return of the eosinophil count to within normal limits, and remains free of cardiovascular events over 24 months.

Probucol inhibits in-stent thrombosis and neointimal hyperplasia by promoting re-endothelialization.

BACKGROUND: Evidence suggests that delayed re-endothelialization is responsible for in-stent thrombosis. Probucol inhibits neointimal thickening in animals via enhanced re-endothelialization and is the only oral drug that consistently inhibits restenosis after coronary angioplasty in humans. Here, we examined the effects of probucol on re-endothelialization and neointimal formation in a stent model. METHODS AND RESULTS: New Zealand White rabbits were fed a hypercholesterolemic diet with probucol (1%) or without (control) (n=11 each) for 6 weeks. At 2 weeks, endothelial denudation and stenting of the iliac artery was performed. Iliac arteries were harvested at week 6, and stented segments sectioned and analyzed. Compared with control, probucol increased in-stent re-endothelialization (74+/-6% in controls versus 93+/-3% in probucol-treated; P=0.008), and decreased average luminal stenosis (58+/-27 versus 31+/-16%; P=0.01) and stent depth (619+/-310 versus 314+/-158 microm; P=0.009). Compared with control, probucol also decreased accumulation of macrophages in the neointima. Furthermore, none of the probucol-treated rabbits had in-stent thrombosis, whereas four of eleven control rabbits showed thrombosis (P=0.04). CONCLUSIONS: Probucol demonstrates anti-restenotic and appears to have anti-thrombotic properties that are likely related to its ability to promote in-stent re-endothelialization.

The role of cardiac MRI in the diagnosis and management of sinus venosus atrial septal defect.

Sinus venosus atrial septal defects (SV-ASDs) are inter-atrial communications caused by a deficiency of the common wall between the superior or inferior vena cava and the right-sided pulmonary veins. The diagnosis can be challenging, especially in adults with delayed presentation. We present images that illustrate an example of the role of cardiac magnetic resonance imaging (CMRI) in the diagnosis and follow-up of a patient with SV-ASD.