Cardiac Complications in Patients Hospitalised With COVID-19 in Australia.

OBJECTIVES: Describe the incidence of cardiac complications in patients admitted to hospital with COVID-19 in Australia. DESIGN: Observational cohort study. SETTING: Twenty-one (21) Australian hospitals. PARTICIPANTS: Consecutive patients aged ≥18 years admitted to hospital with laboratory confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. MAIN OUTCOME MEASURES: Incidence of cardiac complications. RESULTS: Six-hundred-and-forty-four (644) hospitalised patients (62.5±20.1 yo, 51.1% male) with COVID-19 were enrolled in the study. Overall in-hospital mortality was 14.3%. Twenty (20) (3.6%) patients developed new atrial fibrillation or flutter during admission and 9 (1.6%) patients were diagnosed with new heart failure or cardiomyopathy. Three (3) (0.5%) patients developed high grade atrioventricular (AV) block. Two (2) (0.3%) patients were clinically diagnosed with pericarditis or myopericarditis. Among the 295 (45.8%) patients with at least one troponin measurement, 99 (33.6%) had a peak troponin above the upper limit of normal (ULN). In-hospital mortality was higher in patients with raised troponin (32.3% vs 6.1%, p<0.001). New onset atrial fibrillation or flutter (6.4% vs 1.0%, p=0.001) and troponin elevation above the ULN (50.3% vs 16.4%, p<0.001) were more common in patients 65 years and older. There was no significant difference in the rate of cardiac complications between males and females. CONCLUSIONS: Among patients with COVID-19 requiring hospitalisation in Australia, troponin elevation was common but clinical cardiac sequelae were uncommon. The incidence of atrial arrhythmias and troponin elevation was greatest in patients 65 years and older.

Pregnancy Following Heart Transplantation: A Single Centre Case Series and Review of the Literature.

BACKGROUND: Maternal and fetal outcomes of pregnancy amongst cardiac transplant recipients are limited in the current literature. METHODS: We describe five pregnancies in three cardiac transplant recipients managed between a tertiary centre for obstetric medicine and an associated state-wide transplant centre between 2014-2018, and provide a narrative review of the literature. RESULTS: Pre-conception counselling was undertaken. There were no recent rejection episodes and all women demonstrated good baseline cardiac function. Median maternal age was 27 years (range 23-38 yrs.). Median time from transplantation to pregnancy was 5 years (range 2-14 yrs.). All women were managed with modified immunosuppressant regimens and multidisciplinary care. Cardiac function, tacrolimus levels and renal function were closely monitored with frequent monitoring for common complications of pregnancy. There were no maternal or fetal deaths. There was no evidence of graft rejection and no deterioration in cardiac function. Tacrolimus doses were increased to maintain therapeutic targets. Gestational diabetes occurred in three women and cholestasis of pregnancy occurred in one. Each infant was delivered by vaginal delivery. One mother had postpartum haemorrhage in both pregnancies. Pre-eclampsia did not occur. Median gestation at delivery was 37 weeks (range 35+4-40+5 days) with two preterm deliveries. One (1) infant was born with low birth weight. One (1) infant had jaundice requiring phototherapy. All infants were breastfed. CONCLUSION: Pregnancy in transplant recipients confers risk to the mother and fetus. Pre-conception counselling, immunosuppressant tailoring and regular monitoring are paramount to avoid rejection and possible teratogenic complications. Favourable pregnancy outcomes are achievable with specialist multidisciplinary care.

COVID-19 and Acute Heart Failure: Screening the Critically Ill - A Position Statement of the Cardiac Society of Australia and New Zealand (CSANZ).

Up to one-third of COVID-19 patients admitted to intensive care develop an acute cardiomyopathy, which may represent myocarditis or stress cardiomyopathy. Further, while mortality in older patients with COVID-19 appears related to multi-organ failure complicating acute respiratory distress syndrome (ARDS), the cause of death in younger patients may be related to acute heart failure. Cardiac involvement needs to be considered early on in critically ill COVID-19 patients, and even after the acute respiratory phase is passing. This Statement presents a screening algorithm to better identify COVID-19 patients at risk for severe heart failure and circulatory collapse, while balancing the need to protect health care workers and preserve personal protective equipment (PPE). The significance of serum troponin levels and the role of telemetry and targeted transthoracic echocardiography (TTE) in patient investigation and management are addressed, as are fundamental considerations in the management of acute heart failure in COVID-19 patients.

Reliability of thermodilution derived cardiac output with different operator characteristics.

Cardiac output (CO) is commonly measured using the thermodilution technique at the time of right heart catheterisation (RHC). However inter-operator variability, and the operator characteristics which may influence that, has not been quantified. Therefore, this study aimed to assess inter-operator variability with the thermodilution technique using a mock circulation loop (MCL) with calibrated flow sensors. Participants were blinded and asked to determine 4 levels of CO using the thermodilution technique, which was compared with the MCL calibrated flow sensors. The MCL was used to randomly generate CO between 3.0 and 7.0 L/min through changes in heart rate, contractility and vascular resistance with a RHC inserted through the MCL pulmonary artery. Participant characteristics including gender, specialty, age, height, weight, body-mass index, grip strength and RHC experience were recorded and compared to determine their relationship with CO measurement accuracy. In total, there were 15 participants, made up of consultant cardiologists (6), advanced trainees in cardiology (5) and intensive care consultants (4). The majority (9) had performed 26-100 previous RHCs, while 4 had performed more than 100 RHCs. Compared to the MCL-measured CO, participants overestimated CO using the thermodilution technique with a mean difference of +0.75 ± 0.71 L/min. The overall r2 value for actual vs measured CO was 0.85. The difference between MCL and thermodilution derived CO declined significantly with increasing RHC experience (P < 0.001), increasing body mass index (P < 0.001) and decreasing grip strength (P = 0.033). This study demonstrated that the thermodilution technique is a reasonable method to determine CO, and that operator experience was the only participant characteristic related to CO measurement accuracy. Our results suggest that adequate exposure to, and training in, the thermodilution technique is required for clinicians who perform RHC.

Improving medication titration in heart failure by embedding a structured medication titration plan.

BACKGROUND: To improve up-titration of medications to target dose in heart failure patients by improving communication from hospital to primary care. METHODS: This quality improvement project was undertaken within three heart failure disease management (HFDM) services in Queensland, Australia. A structured medication plan was collaboratively designed and implemented in an iterative manner, using methods including awareness raising and education, audit and feedback, integration into existing work practice, and incentive payments. Evaluation was undertaken using sequential audits, and included process measures (use of the titration plan, assignment of responsibility) and outcome measures (proportion of patients achieving target dose) in HFDM service patients with reduced left ventricular ejection fraction. RESULTS: Comparison of the three patient cohorts (pre-intervention cohort A n=96, intervention cohort B n=95, intervention cohort C n=89) showed increase use of the titration plan, a shift to greater primary care responsibility for titration, and an increase in the proportion of patients achieving target doses of angiotensin converting enzyme inhibitors/angiotensin receptor blockers (ACEI/ARB) (A 37% vs B 48% vs C 55%, p=0.051) and beta-blockers (A 38% vs B 33% vs C 51%, p=0.045). Combining all three cohorts, patients not on target doses when discharged from hospital were more likely to achieve target doses of ACEI/ARB (p<0.0001) and beta blockers (p<0.0001) within six months if they received a medication titration plan. CONCLUSIONS: A medication titration plan was successfully implemented in three HFDM services and improved transitional communication and achievement of target doses of evidence-based therapies within six months of hospital discharge.

Right ventricular thrombus detection and multimodality imaging using contrast echocardiography and cardiac magnetic resonance imaging.

We present the case of right ventricular thrombus formation associated with a right ventricular infarct secondary to a proximal right coronary artery thrombus, which was not evident on transthoracic echocardiography but detected on both delayed gadolinium enhanced magnetic resonance imaging and microsphere contrast echocardiography. The diagnosis of right ventricular thrombosis altered the decision to place an implantable cardiac defibrillator in this patient. Anticoagulation with warfarin resulted in resolution of the thrombus. This case highlights the utility of multimodality imaging in the detection and follow-up of right ventricular thrombus in the setting of right ventricular myocardial infarction, and the effectiveness of anticoagulation therapy.

Accuracy of 3-dimensional transoesophageal echocardiography in assessment of prosthetic mitral valve dehiscence with comparison to anatomical specimens.

The evolution of echocardiography from 2-Dimensional Transthoracic Echo through to real time 3-Dimensional Transoesophageal Echo has enabled more accurate visualisation and quantification of valvular disorders especially prosthetic mitral valve paravalvular regurgitation. However, validation of accuracy is rarely confirmed by surgical or post-mortem specimens. We present a case directly comparing different echocardiographic modality images to post mortem specimens in a patient with prosthetic mitral valve paravalvular regurgitation.

Comparison of fluoroscopic versus real-time three-dimensional transthoracic echocardiographic guidance of endomyocardial biopsies.

AIMS: Fluoroscopic-guided right ventricular (RV) endomyocardial biopsy (EMBx) is the conventional method for obtaining myocardial samples to assess for rejection following heart transplantation. This study was designed to assess the feasibility and accuracy of guiding RV sheath and bioptome tip position using real-time three-dimensional echocardiography (RT3DE). METHODS AND RESULTS: Forty EMBx procedures were performed in 21 patients. Five procedures were in a native heart and 35 were performed following cardiac transplantation. A RV long sheath was positioned toward the mid to distal interventricular septum using fluoroscopy. RT3DE was used to correlate sheath tip position with fluoroscopic position. Bioptome tip visualization and position against the endocardium was assessed using RT3DE. Sheath tip location was repositioned in 18 cases (46%) following assessment using RT3DE, due to alignment toward the apex (9) and mid (5) or distal RV (4) free wall. The bioptome tip could be clearly visualized using RT3DE in 83% of passes. In 35% of passes, the bioptome tip was repositioned using RT3DE guidance to improve the sampling site. CONCLUSION: RT3DE-guided EMBx was feasible in the majority of patients and resulted in sheath repositioning in 46% of patients and bioptome tip reorientation in 35% of cases.

Arg389Gly-beta1-adrenergic receptors determine improvement in left ventricular systolic function in nonischemic cardiomyopathy patients with heart failure after chronic treatment with carvedilol.

OBJECTIVE: Administration of the beta-adrenergic receptor blocker carvedilol to patients with chronic heart failure leads to clinically significant benefits, including improvement in left ventricular systolic function in some, but not all, patients. We sought to determine the basis of the variable effect obtained with carvedilol in patients with heart failure. Carvedilol blocks both beta1-adrenergic and beta2-adrenergic receptors, and both receptors exist as polymorphisms. We aimed to determine whether these polymorphisms contribute to variability in response to carvedilol in patients with chronic heart failure. METHODS: We retrospectively and prospectively investigated 135 patients with nonischemic cardiomyopathy and chronic stable heart failure (New York Heart Association class II, III) treated with carvedilol. Baseline echocardiography was obtained before introduction of carvedilol and repeated after stabilization of a maximally tolerated dose of carvedilol (50-100 mg/day) for at least 1 year. Polymerase chain reaction and restriction fragment length polymorphism analysis were used to genotype beta1-adrenergic and beta2-adrenergic receptor polymorphisms. RESULTS: When grouped according to receptor polymorphisms patients were well matched for severity of heart failure, comorbidity and treatment. No significant difference was observed in baseline left ventricular ejection fraction (LVEF) between groups (P>0.05). After 1.5 years of treatment with carvedilol patients with Arg389Arg-beta1-adrenergic receptors had a significantly greater improvement in LVEF compared with Gly389 carriers (Arg389Arg 18.8%; Arg389Gly 9.4%; Gly389Gly 6.0%; P<0.001) whereas there were no differences attributable to other beta1-adrenergic and beta2-adrenergic receptor polymorphisms (P>0.05). CONCLUSION: In patients with nonischemic dilated cardiomyopathy, carvedilol leads to a significantly greater improvement in LVEF in patients with the Arg389Arg-beta1 adrenergic receptor phenotype.