2024 Australia-New Zealand Expert Consensus Statement on Cardiac Amyloidosis

Over the past 5 years, early diagnosis of and new treatments for cardiac amyloidosis (CA) have emerged that hold promise for early intervention. These include non-invasive diagnostic tests and disease modifying therapies. Recently, CA has been one of the first types of cardiomyopathy to be treated with gene editing techniques. Although these therapies are not yet widely available to patients in Australia and New Zealand, this may change in the near future. Given the rapid pace with which this field is evolving, it is important to view these advances within the Australian and New Zealand context. This Consensus Statement aims to update the Australian and New Zealand general physician and cardiologist with regards to the diagnosis, investigations, and management of CA.

Use of Imaging-guided Decongestion for Reducing Heart Failure Readmission and Death in High-risk Patients: A Multi-site Randomized Trial of a Nurse-led Strategy at the Point of Care

BACKGROUND

Nurse-led disease management programs (DMPs) decrease readmission after acute decompensated heart failure (HF). We sought whether readmissions could be further reduced by lung ultrasound (LUS)-guided decongestion before discharge and during DMP.

METHODS AND RESULTS

Of 290 patients hospitalized with acute decompensated HF, 122 at high risk for readmission or mortality were randomized to receive usual care (UC) (n = 64) or UC plus intervention (DMP-Plus) (n = 58), comprising LUS-guided management before discharge and during at-home follow-up. Residual congestion was identified by ≥10 B-lines detected in 8 lung zones. The outcomes included a composite of readmission and/or mortality at 30 and 90 days, and 90-day HF readmission. Residual congestion was detected equally among the patient groups. The 30-day composite outcome occurred in 28% DMP-plus patients and 22% UC patients (odd ratio [OR], 1.36; 95% confidence interval [CI], 0.59-3.1; P = .5) and the 90-day HF readmission outcome occurred in 22% and 31%, respectively (odds ratio, 0.63; 95% CI, 0.28-1.43; P = .3). Residual congestion, identified at predischarge LUS examination in high-risk patients, was associated with early (<14-day) HF readmission (relative risk, 1.19; 95% CI, 1.06-1.32; P = .002) and multiple (≥2) readmissions over 90 days of follow-up (relative risk, 1.09; 95% CI, 1.01-1.16; P = .012), independent of demographics and comorbidities.

CONCLUSIONS

Readmission in patients with incomplete decongestion before discharge occurs within the first 2 weeks. However, our DMP-plus strategy did not improve the primary outcome.

HeartMate 3 implantation with an emphasis on the biventricular configuration

OBJECTIVES

Right ventricular failure following implantation of a durable left ventricular assist device (LVAD) is a major driver of mortality. Reported survival following biventricular (BiVAD) or total artificial heart (TAH) implantation remains substantially inferior to LVAD alone. We report our outcomes with LVAD and BiVAD HeartMate 3 (HM3).

METHODS

Consecutive patients undergoing implantation of an HM3 LVAD between November 2014 and December 2021, at The Alfred, Australia were included in the study. Comparison was made between the BiVAD and LVAD alone groups.

RESULTS

A total of 86 patients, 65 patients with LVAD alone and 21 in a BiVAD configuration underwent implantation. The median age of the LVAD and BiVAD groups was 56 years (Interquartile range 46-62) and 49 years (Interquartile range 37-55), respectively. By 4 years after implantation, 54% of LVAD patients and 43% of BiVAD patients had undergone cardiac transplantation. The incidence of stroke in the entire experience was 3.5% and pump thrombosis 5% (all in the RVAD). There were 14 deaths in the LVAD group and 1 in the BiVAD group. The actuarial survival for LVAD patients at 1 year was 85% and BiVAD patients at 1 year was 95%.

CONCLUSIONS

The application of HM 3 BiVAD support in selected patients appears to offer a satisfactory solution to patients requiring biventricular support.

Hypothermic oxygenated perfusion (HOPE) safely and effectively extends acceptable donor heart preservation times: Results of the Australian and New Zealand trial

BACKGROUND

Cold static storage preservation of donor hearts for periods longer than 4 hours increases the risk of primary graft dysfunction (PGD). The aim of the study was to determine if hypothermic oxygenated perfusion (HOPE) could safely prolong the preservation time of donor hearts.

METHODS

We conducted a nonrandomized, single arm, multicenter investigation of the effect of HOPE using the XVIVO Heart Preservation System on donor hearts with a projected preservation time of 6 to 8 hours on 30-day recipient survival and allograft function post-transplant. Each center completed 1 or 2 short preservation time followed by long preservation time cases. PGD was classified as occurring in the first 24 hours after transplantation or secondary graft dysfunction (SGD) occurring at any time with a clearly defined cause. Trial survival was compared with a comparator group based on data from the International Society of Heart and Lung Transplantation (ISHLT) Registry.

RESULTS

We performed heart transplants using 7 short and 29 long preservation time donor hearts placed on the HOPE system. The mean preservation time for the long preservation time cases was 414 minutes, the longest being 8 hours and 47 minutes. There was 100% survival at 30 days. One long preservation time recipient developed PGD, and 1 developed SGD. One short preservation time patient developed SGD. Thirty day survival was superior to the ISHLT comparator group despite substantially longer preservation times in the trial patients.

CONCLUSIONS

HOPE provides effective preservation out to preservation times of nearly 9 hours allowing retrieval from remote geographic locations.

Type-2 Diabetes and the Clinical Importance of Exaggerated Exercise Blood Pressure

BACKGROUND

Exaggerated exercise blood pressure (EEBP) during clinical exercise testing is associated with poor blood pressure (BP) control and cardiovascular disease (CVD). Type-2 diabetes (T2DM) is thought to be associated with increased prevalence of EEBP, but this has never been definitively determined and was the aim of this study.

METHODS

Clinical exercise test records were analyzed from 13 268 people (aged 53±13 years, 59% male) who completed the Bruce treadmill protocol (stages 1-4, and peak) at 4 Australian public hospitals. Records (including BP) were linked to administrative health datasets (hospital and emergency admissions) to define clinical characteristics and classify T2DM (n=1199) versus no T2DM (n=12 069). EEBP was defined as systolic BP ≥90th percentile at each test stage. Exercise BP was regressed on T2DM history and adjusted for CVD and risk factors.

RESULTS

Prevalence of EEBP (age, sex, preexercise BP, hypertension history, CVD history and aerobic capacity adjusted) was 12% to 51% greater in T2DM versus no T2DM (prevalence ratio [95% CI], stage 1, 1.12 [1.02-1.24]; stage 2, 1.51 [1.41-1.61]; stage 3, 1.25 [1.10-1.42]; peak, 1.18 [1.09-1.29]). At stages 1 to 3, 8.6% to 15.8% (4.8%-9.7% T2DM versus 3.5% to 6.1% no-T2DM) of people with 'normal' preexercise BP (<140/90 mm Hg) were identified with EEBP. Exercise systolic BP relative to aerobic capacity (stages 1-4 and peak) was higher in T2DM with adjustment for all CVD risk factors.

CONCLUSIONS

People with T2DM have higher prevalence of EEBP and exercise systolic BP independent of CVD and many of its known risk factors. Clinicians supervising exercise testing should be alerted to increased likelihood of EEBP and thus poor BP control warranting follow-up care in people with T2DM.

Improvement in functional capacity with spironolactone masks the treatment effect on exercise blood pressure

OBJECTIVES

A hypertensive response to submaximal exercise is associated with cardiovascular disease but this relationship is influenced by functional capacity. Spironolactone improves functional capacity, which could mask treatment effects on exercise blood pressure. This study sought to examine this hypothesis.

DESIGN

Retrospective analysis of a randomized clinical trial.

METHODS

102 participants (54 ± 9 years; 52% male) with a hypertensive response to maximal exercise (systolic BP ≥210 mm Hg men; ≥190 mm Hg women) were randomized to 3-month spironolactone 25 mg daily (n = 53) or placebo (n = 49). Submaximal exercise blood pressure was measured during low-intensity cycling (50, 60 or 70% age-predicted maximal heart rate). Functional capacity was measured as maximal oxygen capacity obtained during a maximal treadmill exercise test, and (resting) aortic stiffness by carotid-to-femoral pulse wave velocity.

RESULTS

Spironolactone improved submaximal exercise systolic blood pressure vs. placebo (-4 ± 16 vs. 2 ± 15 mm Hg, p = 0.045, Cohen's d = 0.42), and had a small (but non-statistically significant) improvement in functional capacity (0.64 ± 5.10 vs. -1.43 ± 5.04 ml/kg/min, p = 0.06, Cohen's d = 0.4). When treatment effects were expressed as the change in submaximal exercise systolic blood pressure relative to the change in functional capacity, a larger effect size was observed (-0.3 ± 1.1 vs. 0.3 ± 1.1 mm Hg/ml·kg·min^-1, p = 0.01, Cohen's d = 0.58), but was not explained by improved aortic stiffness.

CONCLUSIONS

Spironolactone reduces submaximal exercise blood pressure, but this treatment effect may be hidden by improved functional capacity and a non-fixed workload. This highlights the most clinically relevant exercise blood pressure is at a low intensity and fixed workload where the influence of fitness on exercise blood pressure is removed, and the effects of therapy can be appreciated.

Cognitive impairment as a determinant of response to management plans after heart failure admission

AIMS

Cognitive impairment (CI) is highly prevalent in heart failure (HF), and increases patients' risks of readmission. This study sought to determine whether the presence and degree of CI could identify patients most likely to benefit from a HF disease management programme (DMP) to reduce readmissions.

METHODS AND RESULTS

A total of 1152 consecutive Australian patients admitted with HF (2014-2017) were prospectively followed up for 12 months. Of these, 324 patients who received DMP (1-month duration, including post-discharge home visits, medication reconciliation, exercise guidance and early clinical review) were matched (1:2 ratio) with 648 usual care patients. Cognitive function was assessed either on the day of or one day before discharge using the Montreal Cognitive Assessment (MoCA). Outcomes included readmission or death at 1, 3 and 12 months, and days at home within 12 months of discharge. Poorer cognitive function was associated with all adverse outcomes. Compared with usual care, DMP was associated with lower odds of 30-day [odds ratio (OR) 0.60, 95% confidence interval 0.40, 0.91] and 90-day (OR 0.53, 95% confidence interval 0.36, 0.77) readmission or death, and with 19 more days at home within 12 months, independent of HF therapy. The effect sizes of these associations were greater for patients with diminished cognition than those with normal cognition (interaction P = 0.036), and might have been more pronounced among those with mild CI compared with those with more severe CI (MoCA score 17-22; OR 0.42, 95% confidence interval 0.21, 0.87) at 30 days (OR 0.31, 95% confidence interval 0.16, 0.60 at 90 days). Patients with normal cognition had fewer events, irrespective of DMP.

CONCLUSIONS

Cognitive function may determine how HF patients respond to a DMP. Cognitive screening before implementation of a DMP may allow personalized plans for patients with different levels of cognitive function.

The results of a single-center experience with HeartMate 3 in a biventricular configuration

BACKGROUND

Right ventricular (RV) failure after left ventricular assist device (VAD) implantation is a difficult problem. One solution is the implantation of continuous-flow VADs in a biventricular configuration. Disappointing survival and a concerning incidence of right-sided pump thrombosis have been previously reported.

METHODS

From May 2017 to April 2020, a total of 12 patients underwent implantation of HeartMate 3 (HM3) biventricular VADs (BiVADs) as a bridge to cardiac transplantation. The right-sided pump was implanted in the right atrium in all cases. Adverse events and patient outcomes were determined.

RESULTS

Patients were male, and the mean age was 44 years. The etiology was dilated cardiomyopathy (6 patients), sarcoid heart disease (2 patients), ischemic cardiomyopathy (1 patient), anthracycline cardiomyopathy (1 patient), non-compaction cardiomyopathy (1 patient), and arrhythmogenic RV cardiomyopathy with biventricular involvement (1 patient). There was 1 death from multisystem failure. There were 3 episodes of right VAD thrombus (thrombosis or clot ingestion); 1 managed medically, 1 recognized intraoperatively treated with clot retrieval, and 1 requiring pump exchange. There were 3 driveline infections. At 18 months after the procedure, 5 patients (41.7%) had undergone cardiac transplantation, 5 patients (41.7%) were alive and on biventricular support, 1 patient had died (8.3%), and 1 patient had VAD explantation for myocardial recovery (8.3%). Actuarial survival at 18 months was 91.7%.

CONCLUSIONS

In this small study, HM3 BiVAD in these critically ill patients was used with low mortality. This suggests that the timely deployment of biventricular support with HM3 can be associated with favorable outcomes.

Excellent suppression of physiological myocardial FDG activity in patients with cardiac sarcoidosis

INTRODUCTION

Suppression of physiological myocardial FDG activity is vital in patients undergoing PET/CT for assessment of known or suspected cardiac sarcoidosis. This study aims to evaluate the efficacy of physiological myocardial FDG suppression following a protocol change to a 24-h high fat very low carbohydrate (HFVLC) diet and prolonged fast.

METHODS

A retrospective review of patients undergoing FDG PET/CT for the evaluation of cardiac sarcoidosis was performed. Prior to June-2018, patients were prepared with a single very high-fat low carbohydrate meal followed by a 12-18 h fast (group 1). After June-2018, a protocol change was initiated with patients prepared with a HFVLC diet for 24-h followed by a 12-18 h fast (group 2). Focal myocardial activity was classified as positive, absent activity as negative and diffuse/focal on diffuse activity as indeterminate.

RESULTS

A total of 94 FDG PET/CT scans were included with 46 scans in group 1 and 48 scans in group 2. Studies were classified as positive, negative or indeterminate in 25 (54%), 7 (15%) and 14 (30%) scans in group 1 and in 13 (27%), 33 (69%) and 2 (4%) scans in group 2, respectively. In scans classified as negative, myocardial FDG activity was less than mediastinal blood pool activity in 5/7 (71%) scans in group 1 and 33/33 (100%) scans in group 2.

CONCLUSION

Excellent myocardial FDG suppression can be achieved using a 24-h HFVLC diet and prolonged fast, resulting in a very low indeterminate scan rate in patients with known or suspected cardiac sarcoidosis.

Reduction in mortality from implantable cardioverter-defibrillators in non-ischaemic cardiomyopathy patients is dependent on the presence of left ventricular scar

Aims

In patients with non-ischaemic cardiomyopathy (NICM), the mortality benefit of a primary prevention implantable cardioverter-defibrillator (ICD) has been challenged. Left ventricular (LV) scar identified by cardiac magnetic resonance (CMR) imaging is associated with a high risk of malignant arrhythmia in NICM. We aimed to determine the impact of LV scar on the mortality benefit from a primary prevention ICD in NICM.

Methods and results

We recruited 452 consecutive heart failure patients [New York Heart Association (NYHA) Class II/III] with NICM and LV ejection fraction ≤35% from a state-wide CMR service. All patients fulfilled European Society of Cardiology guidelines for primary prevention ICD implantation; however, the decision to implant was at the treating physician's discretion. Baseline clinical and CMR data were recorded prospectively and heart failure mortality risk (MAGGIC score) was calculated. The primary study outcome measurement was all-cause mortality based on presence or absence of ICD, stratified by LV scar. Median follow-up was 37.9 months and there was no difference in MAGGIC score between those who did and did not receive a primary prevention ICD (19.30 ± 5.46 vs. 18.90 ± 5.67, P = 0.50). In patients without LV scar, ICD implantation was not associated with improved mortality [hazard ratio (HR) = 1.22, 95% confidence interval (CI): 0.53-2.78, P = 0.64]. In patients with LV scar, ICD implantation was independently associated with reduced mortality (HR = 0.45, 95% CI: 0.26-0.77, P = 0.003).

Conclusions

In patients with NICM, primary prevention ICD implantation is only associated with reduced mortality in patients with LV scar. This may enable more effective selection of NICM patients for ICD implantation compared with current guidelines.

Measuring atrial stasis during sinus rhythm in patients with paroxysmal atrial fibrillation using 4 Dimensional flow imaging: 4D flow imaging of atrial stasis

BACKGROUND

Paroxysmal atrial fibrillation (PAF) is associated with cardioembolic risk, however events may occur during sinus rhythm (SR). 4D-flow cardiac magnetic resonance (CMR) imaging allows visualisation of left atrial blood flow, to determine the residence time distribution (RTD), an assessment of atrial transit time.

OBJECTIVE

To determine if atrial transit time is prolonged in PAF patients during SR, consistent with underlying atrial stasis.

METHOD

91 participants with PAF and 18 healthy volunteers underwent 4D flow analysis in SR. Velocity fields were produced RTDs, calculated by seeding virtual 'particles' at the right upper pulmonary vein and counting them exiting the mitral valve. An exponential decay curve quantified residence time of particles in the left atrium, and atrial stasis was expressed as the derived constant (RTD_TC) based on heartbeats. The RTD_TC was evaluated within the PAF group, and compared to healthy volunteers.

RESULTS

Patients with PAF (n = 91) had higher RTD_TC compared with gender-matched controls (n = 18) consistent with greater atrial stasis (1.68 ± 0.46 beats vs 1.51 ± 0.20 beats; p = .005). PAF patients with greater thromboembolic risk had greater atrial stasis (median RTD_TC of 1.72 beats in CHA₂DS₂-VASc≥2 vs 1.52 beats in CHA₂DS₂-VASc<2; p = .03), only female gender and left ventricular ejection fraction contributed significantly to the atrial RTD_TC (p = .006 and p = .023 respectively).

CONCLUSIONS

Atrial stasis quantified by 4D flow is greater in PAF, correlating with higher CHA₂DS₂-VASc scores. Female gender and systolic dysfunction are associated with atrial stasis. RTD offers an insight into atrial flow that may be developed to provide a personalised assessment of thromboembolic risk.

Impact of sex, socio-economic status, and remoteness on therapy and survival in heart failure

Aims

This study aims to determine if traditional markers of disadvantage [female sex, low socio‐economic status (SES), and remoteness] are associated with lower prescription of evidence‐based therapy and higher mortality among patients with moderate–severe heart failure with reduced ejection fraction.

Methods and results

We recruited 452 consecutive class II–III heart failure with reduced ejection fraction patients. Baseline clinical data were recorded prospectively. The primary outcome was the association of female sex on overall survival. Secondary outcomes included association between evidence‐based therapy delivery and sex and association of SES and remoteness on heart failure therapy and survival. The Australian Bureau of Statistics generated all indices. Median follow‐up was 37.9 months. One hundred and nine patients (24.3%) were women. There was no difference in overall survival based on sex (hazard ratio = 1.19, 95% confidence interval: 0.74–1.92, 0.48). There was no difference in prescription of beta‐blockers [χ²(1) = 0.91, 0.66], angiotensin‐converting enzyme inhibitors [χ²(1) = 0.001, 0.97], nor aldosterone antagonists [χ²(1) = 2.71, 0.10]. There was no difference in rates of primary prevention implantable cardioverter‐defibrillator implantation in men compared with women [χ²(1) = 0.35, 0.56]. Neither higher SES nor inner city residence conferred an overall survival benefit.

Conclusions

In this Australian cohort of heart failure patients, delivery of care and likelihood of death are comparable between the sexes, SES groups, and rural vs. city residents.

The ventricular residence time distribution derived from 4D flow particle tracing: a novel marker of myocardial dysfunction

4D flow cardiac magnetic resonance (CMR) imaging allows visualisation of blood flow in the cardiac chambers and great vessels. Post processing of the flow data allows determination of the residence time distribution (RTD), a novel means of assessing ventricular function, potentially providing additional information beyond ejection fraction. We evaluated the RTD measurement of efficiency of left and right ventricular (LV and RV) blood flow. 16 volunteers and 16 patients with systolic dysfunction (LVEF < 50%) underwent CMR studies including 4D flow. The RTDs were created computationally by seeding virtual 'particles' at the inlet plane in customised post-processing software, moving these particles with the measured blood velocity, recording and counting how many exited per unit of time. The efficiency of ventricular flow was determined from the RTDs based on the time constant (RTDc = - 1/B) of the exponential decay. The RTDc was compared to ejection fraction, T1 mapping and global longitudinal strain (GLS). There was a significant difference between groups in LV RTDc (healthy volunteers 1.2 ± 0.13 vs systolic dysfunction 2.2 ± 0.80, p < 0.001, C-statistic = 1.0) and RV RTDc (1.5 ± 0.15 vs 2.0 ± 0.57, p = 0.013, C-statistic = 0.799). The LV RTDc correlated significantly with LVEF (R = - 0.84, P < 0.001) and the RV RTDc had significant correlation with RVEF (R = - 0.402, p = 0.008). The correlation between LV RTDc and LVEF was similar to GLS and LVEF (0.926, p < 0.001). The ventricular residence time correlates with ejection fraction and can distinguish normal from abnormal systolic function. Further assessment of this method of assessment of chamber function is warranted.

Validation of Predictive Score of 30-Day Hospital Readmission or Death in Patients With Heart Failure

Existing prediction algorithms for the identification of patients with heart failure (HF) at high risk of readmission or death after hospital discharge are only modestly effective. We sought to validate a recently developed predictive model of 30-day readmission or death in HF using an Australia-wide sample of patients. This study used data from 1,046 patients with HF at teaching hospitals in 5 Australian capital cities to validate a predictive model of 30-day readmission or death in HF. Besides standard clinical and administrative data, we collected data on individual sociodemographic and socioeconomic status, mental health (Patient Health Questionnaire [PHQ]-9 and Generalized Anxiety Disorder [GAD]-7 scale score), cognitive function (Montreal Cognitive Assessment [MoCA] score), and 2-dimensional echocardiograms. The original sample used to develop the predictive model and the validation sample had similar proportions of patients with an adverse event within 30 days (30% vs 29%, p = 0.35) and 90 days (52% vs 49%, p = 0.36). Applying the predicted risk score to the validation sample provided very good discriminatory power (C-statistic = 0.77) in the prediction of 30-day readmission or death. This discrimination was greater for predicting 30-day death (C-statistic = 0.85) than for predicting 30-day readmission (C-statistic = 0.73). There was a small difference in the performance of the predictive model among patients with either a left ventricular ejection fraction of <40% or a left ventricular ejection fraction of ≥40%, but an attenuation in discrimination when used to predict longer-term adverse outcomes. In conclusion, our findings confirm the generalizability of the predictive model that may be a powerful tool for targeting high-risk patients with HF for intensive management.

Cardiac magnetic resonance imaging in suspected blunt cardiac injury: A prospective, pilot, cohort study

INTRODUCTION

The aim of this study was to evaluate the incidence and severity of blunt cardiac injury (BCI) as determined by cardiac magnetic resonance imaging (CMR), and to compare this to currently used diagnostic methods in severely injured patients.

MATERIALS AND METHODS

We conducted a prospective, pilot cohort study of 42 major trauma patients from July 2013 to Jan 2015. The cohort underwent CMR within 7 days, enrolling 21 patients with evidence of chest injury and an elevated Troponin I compared to 21 patients without chest injury who acted as controls. Major adverse cardiac events (MACE) including ventricular arrhythmia, unexplained hypotension requiring inotropes, or a requirement for cardiac surgery were recorded.

RESULTS

6/21 (28%) patients with chest injuries had abnormal CMR scans, while all 21 control patients had normal scans. CMR abnormalities included myocardial oedema, regional wall motion abnormalities, and myocardial haemorrhage. The left ventricle was the commonest site of injury (5/6), followed by the right ventricle (2/6) and tricuspid valve (1/6). MACE occurred in 5 patients. Sensitivity and specificity values for CMR at predicting MACE were 60% (15-95) and 81% (54-96), which compared favourably with other tests.

CONCLUSION

In this pilot trial, CMR was found to give detailed anatomic information of myocardial injury in patients with suspected BCI, and may have a role in the diagnosis and management of patients with suspected BCI.

Mild cognitive impairment predicts death and readmission within 30days of discharge for heart failure

BACKGROUND

Cognitive impairment is highly prevalent in heart failure (HF), and may be associated with short-term readmission. This study investigated the role of cognition, incremental to other clinical and non-clinical factors, independent of depression and anxiety, in predicting 30-day readmission or death in HF.

METHODS

This study followed 565 patients from an Australia-wide HF longitudinal study. Cognitive function (MoCA score) together with standard clinical and non-clinical factors, mental health and 2D echocardiograms were collected before hospital discharge. The study outcomes were death and readmission within 30days of discharge. Logistic regression, Harrell's C-statistic, integrated discrimination improvement (IDI) and net reclassification index were used for analysis.

RESULTS

Among 565 patients, 255 (45%) had at least mild cognitive impairment (MoCA≤22). Death (n=43, 8%) and readmission (n=122, 21%) within 30days of discharge were more likely to occur among patients with mild cognitive impairment (OR=2.00, p=0.001). MoCA score was also negatively associated with 30-day readmission or death (OR=0.91, p<0.001) independent of other risk factors. Adding MoCA score to an existing prediction model of 30-day readmission significantly improved discrimination (C-statistic=0.715 vs. 0.617, IDI estimate 0.077, p<0.001). From prediction models developed from our study, adding MoCA score (C-statistic=0.83) provided incremental value to that of standard clinical and non-clinical factors (C-statistic=0.76) and echocardiogram parameters (C-statistic=0.81) in predicting 30-day readmission or death. Reclassification analysis suggests that addition of MoCA score improved classification for a net of 12% of patients with 30-day readmission or death and of 6% of patients without (p=0.002).

CONCLUSIONS

Mild cognitive impairment predicts short-term outcomes in HF, independent of clinical and non-clinical factors.

Diffuse Ventricular Fibrosis on Cardiac Magnetic Resonance Imaging Associates With Ventricular Tachycardia in Patients With Hypertrophic Cardiomyopathy

INTRODUCTION

Non-sustained ventricular tachycardia (NSVT) is a risk factor for sudden cardiac death (SCD) in patients with hypertrophic cardiomyopathy (HCM). We aimed to assess whether diffuse ventricular fibrosis on cardiac magnetic resonance (CMR) imaging could be a surrogate marker for ventricular arrhythmias in patients with HCM.

METHODS

A total of 100 patients with HCM (mean age 51 ± 13 years, septal wall thickness 20 ± 5 mm) underwent CMR with a 1.5 T scanner to determine the presence of ventricular late gadolinium enhancement (LGE) for focal fibrosis, and post-contrast T1 mapping for diffuse ventricular fibrosis. The presence of NSVT was determined by Holter monitoring and a subset of high risk patients received an implantable cardioverter-defibrillator (ICD).

RESULTS

NSVT was detected in 23 of 100 patients with HCM. Focal ventricular fibrosis (by LGE) was observed in 87%, with no significant difference between patients with (96%) or without NSVT (86%, P = 0.19). However, LGE mass was greater in patients with (16.5 ± 19.1 g) versus without NSVT (7.6 ± 10.2 g, P < 0.01). NSVT was associated with a significant reduction in ventricular T1 relaxation time (422 ± 54 milliseconds) versus patients without NSVT (512 ± 115 milliseconds; P < 0.001). There was significant reduction in ventricular T1 relaxation time in patients with (430 ± 48 milliseconds) versus without aborted SCD (495 ± 113 milliseconds; P = 0.01) over a mean follow-up of 40 ± 10 months. On multivariate analysis post-contrast ventricular T1 relaxation time and septal wall thickness were the only predictors of NSVT.

CONCLUSION

Post-contrast T1 relaxation time on CMR is associated with ventricular arrhythmias in patients with HCM. Diffuse ventricular fibrosis may be an important marker of arrhythmic risk in patients with HCM.

Subclinical LV dysfunction and 10-year outcomes in type 2 diabetes mellitus

OBJECTIVE

New imaging techniques have permitted the detection of subclinical LV dysfunction (LVD) in up to half of patients with type 2 diabetes mellitus (DM) with a normal EF. However, the connection between early LVD and prognosis is unclear. This study aimed to define the long-term outcome of LVD associated with type 2 DM.

METHODS

In this prospective cohort study, 230 asymptomatic patients with type 2 DM underwent measurement of global longitudinal 2D strain (GLS) for detection of LVD and were followed for up to 10 years. All subjects had normal EF (≥50%) and no evidence of coronary artery disease at recruitment. Outcome data were obtained through centralised state-wide death and hospital admission registries. The primary endpoint was all-cause mortality and hospitalisation.

RESULTS

On study entry, almost half (45%) of the cohort had evidence of LVD as detected by GLS. Over a median follow-up of 7.4±2.6 years (range 0.6-9.7 years), 68 patients (30%) met the primary endpoint (LVD: 37%; normal LV function: 24%). GLS was independently associated with the primary endpoint (HR=1.10; p=0.04), as was systolic blood pressure (HR=1.02; p<0.001) and levels of glycosylated haemoglobin (HR=1.28; p=0.011). Patients with LVD had significantly worse outcome than those without (χ(2)=4.73; p=0.030).

CONCLUSIONS

Subclinical LVD is common in asymptomatic patients with type 2 DM, is readily detectable by GLS imaging and is independently associated with adverse outcome.

TRIAL REGISTRATION NUMBER

Australian and New Zealand Clinical Trials Registry (ACTRN12612001178831).

Asymptomatic myocarditis during clozapine re-titration, in a patient who had previously been stable on clozapine for 10 years

OBJECTIVE

We present a case of confirmed clozapine-induced myocarditis in a patient who was not naïve to the drug.

METHOD

This patient, who had been stable on clozapine for 10 years, relapsed following self-cessation. Asymptomatic throughout inpatient re-titration, serum cardiac enzymes were nonetheless routinely taken.

RESULTS

Occult myocarditis was only discovered due to an elevated Troponin I, and was confirmed by cardiac imaging.

CONCLUSIONS

Once thought to be the preserve of initial exposure to the medication, clozapine-induced myocarditis can occur at any re-titration point if the immunological milieu permits. We therefore recommend routine monitoring of serum cardiac enzymes with all patients undergoing titration of clozapine, regardless of whether they have previously been stable on the drug.

A comprehensive evaluation of myocardial fibrosis in hypertrophic cardiomyopathy with cardiac magnetic resonance imaging: linking genotype with fibrotic phenotype

AIMS

In hypertrophic cardiomyopathy (HCM), attempts to associate genotype with phenotype have largely been unsuccessful. More recently, cardiac magnetic resonance (CMR) imaging has enhanced myocardial fibrosis characterization, while next-generation sequencing (NGS) can identify pathogenic HCM mutations. We used CMR and NGS to explore the link between genotype and fibrotic phenotype in HCM.

METHODS AND RESULTS

One hundred and thirty-nine patients with HCM and 25 healthy controls underwent CMR to quantify regional myocardial fibrosis with late gadolinium enhancement (LGE) and diffuse myocardial fibrosis with post-contrast T1 mapping. Collagen content of myectomy specimens from nine HCM patients was determined. Fifty-six HCM patients underwent NGS for 65 cardiomyopathy genes, including 36 HCM-associated genes. Post-contrast myocardial T1 time correlated histologically with myocardial collagen content (r = -0.70, P = 0.03). Compared with controls, HCM patients had more LGE (4.6 ± 6.1 vs. 0%, P < 0.001) and lower post-contrast T1 time (483 ± 83 vs. 545 ± 49 ms, P < 0.001). LGE negatively correlated with left-ventricular (LV) ejection fraction and outflow tract obstruction, whereas lower post-contrast T1 time, suggestive of more diffuse myocardial fibrosis, was associated with LV diastolic impairment and dyspnoea. Patients with identifiable HCM mutations had more LGE (7.9 ± 8.6 vs. 3.1 ± 4.3%, P = 0.03), but higher post-contrast T1 time (498 ± 81 vs. 451 ± 70 ms, P = 0.03) than patients without.

CONCLUSION

In HCM, contrast-enhanced CMR with T1 mapping can non-invasively evaluate regional and diffuse patterns of myocardial fibrosis. These patterns of fibrosis occur independently of each other and exhibit distinct clinical associations. HCM patients with recognized genetic mutations have significantly more regional, but less diffuse myocardial fibrosis than those without.

Diffuse ventricular fibrosis is a late outcome of tachycardia-mediated cardiomyopathy after successful ablation

BACKGROUND

Successful arrhythmia ablation normalizes ejection fraction (EF) in tachycardia-mediated cardiomyopathy, but recurrent heart failure and late sudden death have been reported. The aim of this study was to characterize the left ventricle (LV) of tachycardia-mediated cardiomyopathy patients long after definitive arrhythmia cure.

METHODS AND RESULTS

Thirty-three patients with a history of successfully ablated incessant focal atrial tachycardia 64±36 months prior, and 20 healthy controls were recruited. At ablation, 18 patients had EF<50% (AT-low EF) that recovered within 3 months from 37±12 to 56±4% (P<0.001), whereas 15 patients had EF>55% (AT-normal EF). No subjects had EF of 50% to 55%. Subjects underwent echocardiography with speckle tracking and contrast-enhanced cardiac MRI with ventricular T1 mapping as an index of diffuse fibrosis. Contrast-enhanced cardiac MRI was performed using a clinical 1.5-T scanner and 0.2 mmol/kg gadolinium-diethylene triamine penta-acetic acid for contrast. Subject characteristics were similar across the 3 groups. Compared with AT-normal EF patients and controls, AT-low EF patients had lower EF (60±6 versus 64±4 and 65±4%; P<0.05), greater indexed LV end-diastolic volume (102±34 versus 84±14 and 85±16 mL/m(2); P<0.05), and greater indexed LV end-systolic volume (41±11 versus 31±7 and 30±8 mL/m(2); P<0.01) on contrast-enhanced cardiac MRI. Compared with controls, AT-low EF patients had reduced global LV corrected T1 time (442±53 versus 529±61; P<0.05) consistent with diffuse fibrosis.

CONCLUSIONS

Tachycardia-mediated cardiomyopathy patients exhibit differences in LV structure and function including diffuse fibrosis long after arrhythmia cure, indicating that recovery is incomplete.

Impact of spironolactone on vascular, myocardial, and functional parameters in untreated patients with a hypertensive response to exercise

BACKGROUND

Although a hypertensive response to exercise (HRE) is associated with cardiac risk and masked hypertension (MHT), its mechanisms and appropriate treatment remain unclear. We investigated spironolactone as a treatment for abnormal vascular and myocardial stiffness in HRE.

METHODS

In this randomized, double-blind, placebo-controlled study of 115 patients (54 ± 9 years, 57% men) with an HRE (≥210/105 mm Hg in men; ≥190/105 mm Hg in women) but no prior history of hypertension or myocardial ischemia, MHT prevalence was 40%. Patients were randomized to spironolactone 25mg daily (n = 58) or placebo (n = 57) and underwent evaluation at baseline and 3 months with exercise echocardiography, VO2max, pulse wave velocity (PWV), exercise and central blood pressure (BP), and 24-hour ambulatory BP. Changes in left ventricular mass index (LVMI), Doppler-derived E/em ratio (LV filling pressure), and myocardial strain were assessed.

RESULTS

Baseline 24-hour systolic BP (SBP) was 133 ± 10 mm Hg and peak-exercise SBP was 219 ± 16 mm Hg. Peak systolic strain (0.3 ± 3.6% vs. -0.1 ± 3.2, P = 0.56), E/em (-1.1 ± 2.3 vs. -0.6 ± 1.7, P = 0.30), VO(2max) (0.4 ± 4.9 vs. -0.9 ± 4.1 ml/kg/min, P = 0.15), and adjusted PWV did not significantly change with treatment, despite reduction in exercise SBP, 24-hour SBP, and LVMI. The change in exercise E/em was of borderline significance (-0.3 ± 2.4 vs. 0.8 ± 2.8, P = 0.06) and became significant after adjustment for baseline differences (P = 0.01). Patients with higher LVMI significantly increased VO(2max) (1.1 ± 5.6 vs. -2.4 ± 4.4 ml/kg/min, P < 0.05) and reduced exercise E/e(m) (-0.7 ± 2.7 vs. 1.9 ± 2.8, P < 0.05).

CONCLUSIONS

In HRE patients without previous hypertension, short-term spironolactone reduced exercise BP, 24-hour ambulatory BP, LVMI, and E/e(m) but did not significantly alter exercise capacity or myocardial strain.

Recurrent myocarditis--an important mimic of ischaemic myocardial infarction

Patients presenting with a syndrome of chest pain, elevated cardiac enzyme levels with or without electrocardiogram changes are a common diagnostic and management problem in cardiology. Most commonly, this is due to ischaemic myocardial infarction secondary to coronary artery disease. However, when coronary angiography does not demonstrate any obstructive coronary artery lesion, the diagnosis of myocarditis should be considered. Cardiac magnetic resonance imaging is helpful towards making this diagnosis. Here, we describe the first reported Australian cases of recurrent myocarditis presenting with ischaemic chest pain and elevated cardiac enzyme levels. These cases serve as an important reminder to clinicians that myocarditis is an important mimic of ischaemic myocardial infarction.

Diffuse myocardial fibrosis in hypertrophic cardiomyopathy can be identified by cardiovascular magnetic resonance, and is associated with left ventricular diastolic dysfunction

BACKGROUND

The presence of myocardial fibrosis is associated with worse clinical outcomes in hypertrophic cardiomyopathy (HCM). Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) sequences can detect regional, but not diffuse myocardial fibrosis. Post-contrast T(1) mapping is an emerging CMR technique that may enable the non-invasive evaluation of diffuse myocardial fibrosis in HCM. The purpose of this study was to non-invasively detect and quantify diffuse myocardial fibrosis in HCM with CMR and examine its relationship to diastolic performance.

METHODS

We performed CMR on 76 patients - 51 with asymmetric septal hypertrophy due to HCM and 25 healthy controls. Left ventricular (LV) morphology, function and distribution of regional myocardial fibrosis were evaluated with cine imaging and LGE. A CMR T(1) mapping sequence determined the post-contrast myocardial T(1) time as an index of diffuse myocardial fibrosis. Diastolic function was assessed by transthoracic echocardiography.

RESULTS

Regional myocardial fibrosis was observed in 84% of the HCM group. Post-contrast myocardial T(1) time was significantly shorter in patients with HCM compared to controls, consistent with diffuse myocardial fibrosis (498 ± 80 ms vs. 561 ± 47 ms, p < 0.001). In HCM patients, post-contrast myocardial T(1) time correlated with mean E/e' (r = -0.48, p < 0.001).

CONCLUSIONS

Patients with HCM have shorter post-contrast myocardial T(1) times, consistent with diffuse myocardial fibrosis, which correlate with estimated LV filling pressure, suggesting a mechanistic link between diffuse myocardial fibrosis and abnormal diastolic function in HCM.

Application of an exercise intervention on the evolution of diastolic dysfunction in patients with diabetes mellitus: efficacy and effectiveness

BACKGROUND

Diastolic dysfunction (DD) is associated with adverse cardiovascular outcomes. We studied the impact of an exercise-based lifestyle intervention on the evolution of DD in patients with type 2 diabetes mellitus (T2DM) and prospectively investigated the clinical correlates of DD progression.

METHODS AND RESULTS

A total of 223 outpatients with T2DM were randomized to supervised exercise-based lifestyle intervention (initial gym-based program and lifestyle and diet advice followed by telephone-guided supervision) or usual care. Patients underwent echocardiographic assessment of diastolic function and metabolic and clinical evaluation at baseline and 3 years. Changes in prevalence and evolution of DD were assessed and correlations sought with clinical and metabolic variables. DD was present in 50% of patients at baseline and 54% at 3 years, with no difference between the usual care and intervention groups (60% versus 48%, P=0.10). Abnormal DD at the final visit was independently associated with older age and a decrease in peak oxygen consumption over time (P<0.05). There was no impact on glycemic control or exercise capacity. In a subanalysis restricted to patients who finished the full 3-year follow-up, control subjects were independently associated with DD at 3 years (β=0.90; odds ratio, 2.46; P=0.034), with the only other independent correlate being older age (β=0.05; odds ratio, 1.06; P=0.019).

CONCLUSIONS

Despite being efficacious in the subgroup who completed 3 years of exercise-based lifestyle intervention, randomization to this program was not effective in reducing progression of subclinical DD in patients with T2DM, which may reflect the recognized difficulty of adherence to prolonged exercise intervention.

CLINICAL TRIAL REGISTRATION

URL: http://www.anzctr.org.au. Unique identifier: ACTRN12607000060448.

Use of myocardial deformation imaging to detect preclinical myocardial dysfunction before conventional measures in patients undergoing breast cancer treatment with trastuzumab

BACKGROUND

Trastuzumab prolongs survival in patients with human epidermal growth factor receptor type 2-positive breast cancer. Sequential left ventricular (LV) ejection fraction (EF) assessment has been mandated to detect myocardial dysfunction because of the risk of heart failure with this treatment. Myocardial deformation imaging is a sensitive means of detecting LV dysfunction, but this technique has not been evaluated in patients treated with trastuzumab. The aim of this study was to investigate whether changes in tissue deformation, assessed by myocardial strain and strain rate (SR), are able to identify LV dysfunction earlier than conventional echocardiographic measures in patients treated with trastuzumab.

METHODS

Sequential echocardiograms (n = 152) were performed in 35 female patients (51 +/- 8 years) undergoing trastuzumab therapy for human epidermal growth factor receptor type 2-positive breast cancer. Left ventricular EF was measured by 2- and 3-dimensional (2D and 3D) echocardiography, and myocardial deformation was assessed using tissue Doppler imaging and 2D-based (speckle-tracking) strain and SR. Change over time was compared every 3 months between baseline and 12 months.

RESULTS

There was no overall change in 3D-EF, 2D-EF, myocardial E-velocity, or strain. However, there were significant reductions seen in tissue Doppler imaging SR (P < .05), 2D-SR (P < .001), and 2D radial SR (P < .001). A drop > or =1 SD in 2D longitudinal SR was seen in 18 (51%) patients; 13 (37%) had a similar drop in radial SR. Of the 18 patients with reduced longitudinal SR, 3 had a concurrent reduction in EF > or =10%, and another 2 showed a reduction over 20 months follow-up.

CONCLUSIONS

Myocardial deformation identifies preclinical myocardial dysfunction earlier than conventional measures in women undergoing treatment with trastuzumab for breast cancer.

Association of myocardial strain with left ventricular geometry and progression of hypertensive heart disease

Different patterns of abnormal left ventricular (LV) geometry are associated with variations in prognosis, but the mechanisms of these effects remain undefined. We investigated the association of myocardial deformation with these findings and their evolution. Two-dimensional echocardiography was performed in 85 hypertensive patients referred for serial evaluation (age 58 +/- 13 years, 48% male). LV mass index and regional wall thickness were used to assign patients into groups with normal geometry, concentric remodeling, concentric hypertrophy, and eccentric hypertrophy. Septal strain and strain rate were measured using velocity vector imaging. The evolution of morphological changes was followed over 2.7 +/- 1.3 years. Analysis of LV geometry revealed normal geometry in 13 patients (15%), concentric remodeling in 20 (24%), concentric hypertrophy in 42 (49%), and eccentric hypertrophy in 10 (12%). Overall strain was -13.6 +/- 4.5%, and strain rate was -0.65 +/- 0.24/second. Strain was significantly lower in patients with concentric remodeling (-12.8 +/- 4.2%) or concentric hypertrophy (-12.5 +/- 4.1%) compared with patients with normal geometry (-17.5 +/- 5.5%, p < or =0.05), and these associations were independent of blood pressure. Strain rate was also significantly reduced in patients with concentric hypertrophy (p < or =0.01). There were no significant differences in baseline strain, wall stress, blood pressure, or age between patients who changed LV geometric class and those who did not. In conclusion, baseline myocardial tissue deformation, but not evolution, is associated with LV geometry in treated hypertensive patients.

Performance of conventional echocardiographic parameters and myocardial measurements in the sequential evaluation of left ventricular function

Echocardiography is frequently used for sequential evaluation of left ventricular (LV) function, although the reproducibility of such conventional measurements as LV ejection fraction (EF) have been questioned. The utility of such newer measurements as tissue Doppler imaging and left atrial (LA) size in serial clinical testing are undefined. The magnitude and clinical relevance of changes in conventional and new measurements of LV function were investigated and compared in 346 consecutive patients undergoing sequential echocardiography. Change in LA area, LVEF, tissue E velocity (Em), and transmitral E to Em ratio (E/Em) were compared over 304 +/- 239 days. Changes within and between parameters (after mean correction to make measurements comparable) were assessed in groups designated as stable (n = 144) or unstable (n = 202) according to clinical progress. A single observer remeasured these parameters in stable patients individually and with paired studies side by side. Significant variability was seen in all measurements, with change in LVEF the only parameter differing between stable and unstable groups (6.4 +/- 8.9% vs 9.4 +/- 5.4%; p <0.001). Tissue Em and E/Em ratio were more variable than LA area or LVEF. In stable patients, LVEF changed the least and E/Em changed the most over time (p <0.05). With a single blinded observer, Em had improved reproducibility (1.5 +/- 1.9 vs 2.3 +/- 2.6 cm/s; p <0.001), as did visual EF. In conclusion, variability in all measurements was high irrespective of clinical status. Newer measurements were no better than LVEF in detecting changes in clinical status. Sequential LV assessment should be interpreted with caution, and more robust measurements are needed.

Feasibility and clinical decision-making with 3D echocardiography in routine practice

OBJECTIVE

To assess the feasibility and potential impact of routine three-dimensional (3D) echocardiographic assessment of left ventricular (LV) ejection fraction and volumes on clinical decision-making.

METHODS

Patients referred to three hospital-based echocardiography laboratories underwent 2D echocardiography (2DE) and 3D echocardiography (3DE). Feasibility was assessed in a group of 168 unselected patients and decision-making assessed within an expanded group of 220 patients. The time for acquisition and measurement was obtained. Feasibility was defined by ability to measure LV parameters. The potential of 3DE to alter clinical decisions based on 2DE was evaluated by the ability to identify four clinically relevant measurement thresholds: (1) LV end-systolic volume (LVESV) >50 ml/m(2) (indication for surgery in regurgitant valve disease); (2) LVESV >30 ml/m(2) (prognosis after infarction); (3) LV ejection fraction (LVEF) <35% (indication for implantable defibrillator); and (4) LVEF <40% (indication for heart failure treatment).

RESULTS

3DE was technically feasible in 83% of unselected patients. The additional time for 3D acquisition and measurement was available in 184 patients and was 5.4 (SD 2.0) minutes. The use of 3DE changed categorisation in between 6-11% of patients. Within threshold categories, 3D reallocated 17.5% (11/63) of patients with LVEF <35%, 16.1% (13/81) for LVEF <40%, 12.4% (13/105) for LVESV >30 ml/m(2) and 8.5% (5/59) for LVESV >50 ml/m(2). Most of the impact of 3D was within 10 ml/m(2) of selected volume thresholds (>or=75%) and 10% of EF thresholds (>80%).

CONCLUSION

Measurement of LV volumes and EF by 3DE is clinically feasible and has the potential to significantly alter clinical decision-making.

Comparison of four automated hematology analyzers

OBJECTIVE

To compare four automated hematology analyzers for efficiency and sensitivity.

DESIGN

Four automated hematology analyzers were compared in a side by side study: Bayer ADVIA 120 (Bayer Diagnostic Division, Tarrytown, NY), Beckman Coulter GEN S (Beckman Coulter, Brea, CA), Abbott CELL DYN 3500 and CELL DYN 4000 (Abbott Diagnostics, Santa Clara, CA). 164 specimens were analyzed for cell counts, indices, and the automated WBC differential (DLC). Tallies were kept of all interventions, defined as any parameter necessitating examination of a stained blood smear by a clinical laboratory scientist. A 400-cell manual differential was performed on each specimen and used as the reference to prepare truth tables for each type of WBC.

PATIENTS

Specimens comprised regular runs from this tertiary care teaching hospital. These included inpatients, outpatients, and oncology patients, including bone marrow transplant patients.

MAIN OUTCOME MEASURES

Results from the truth tables were used for calculating sensitivity and efficiency for each analyzer. Each DLC parameter was analyzed for variance using the one-way ANOVA test.

RESULTS

No intervention was required for 103 of 164 specimens for the CELL DYN 3500; the ADVIA gave 70 reportable DLCs without intervention, the GEN S provided 91 and the CELL DYN 4000 resulted in 117 of 164 DLCs without intervention. Agreement or efficiency was 65% for the CELL DYN 3500, 41% for the ADVLA, 58% for the GEN S, and 79% for the CELL DYN 4000. Sensitivity was 67% for the CELL DYN 3500, 86% for the ADVIA, 76% for the GEN S, and 71% for the CELL DYN 4000. Probability of significant variation was as follows for each parameter: % neutrophil 0.8747, % lymphocyte 0.8830, % monocyte 0.0296, % eosinophil 0.7903, and % basophil <.0001.

CONCLUSION

The analyzers tested were acceptable for routine laboratory work. Selection would depend on individual need with respect to sensitivity and efficiency. The clinical significance of disagreement between the DLC and the manual differential remains to be determined.