Comparison of electrographic changes, clinical features and outcomes in different variants of Takotsubo syndrome.

BACKGROUND: Dysfunction of the left ventricular (LV) apex (apical variant) is the most common form in Takotsubo syndrome (TS). Several less common non-apical variants have been described - mid-ventricular, basal and focal. We hypothesised that the clinical presentation, and electrocardiographic (ECG) findings may vary between apical and non-apical TS. METHODS: We prospectively identified 194 consecutive patients with TS presenting to Middlemore Hospital, Auckland and obtained clinical, echocardiography, coronary angiography, and long-term follow-up data. ECGs at admission and Day 1 were compared. RESULTS: Of 194 patients with TS, 168 (86.6%) had apical TS, and 26 (13.4%) non-apical TS (11 mid-ventricular TS, 5 basal TS, 10 focal TS). Apical TS patients had more significant LV systolic impairment (p = 0.001) and longer length of stay (p = 0.001). The extent of T-wave inversion (TWI) was similar for both groups on admission (p = 0.88). By Day 1 the extent of TWI was greater in apical TS group (median number of leads 5 vs. 1, p = 0.02). The change in QTc interval between admission and Day 1 was greater in apical TS group (29.7 ms vs. 2.77 ms, p < 0.001). Composite in-hospital complication rate was similar for both groups (13.7% vs. 15.4%, p = 0.77). CONCLUSIONS: Compared with non-apical variants, apical TS patients develop more extensive TWI and greater QT prolongation on ECG, and more significant LV systolic impairment, but in-hospital complications were similar. Clinicians should be aware that there is a sub-group of TS patients who have non-apical regional wall motion abnormalities and who don't develop ECG changes typical of the more common apical variant.

Implantable cardioverter defibrillator and cardiac resynchronization therapy use in New Zealand (ANZACS-QI 33).

BACKGROUND: The ANZACS-QI Cardiac Implanted Device Registry (ANZACS-QI DEVICE) collects nationwide data on cardiac implantable electronic devices in New Zealand (NZ). We used the registry to describe contemporary NZ use of implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT). METHODS: All ICD and CRT Pacemaker implants recorded in ANZACS-QI DEVICE between 1 January 2014 and 31 December 2017 were analyzed. RESULTS: Of 1579 ICD implants, 1152 (73.0%) were new implants, including 49.0% for primary prevention and 51.0% for secondary prevention. In both groups, median age was 62 years and patients were predominantly male (81.4% and 79.2%, respectively). Most patients receiving a primary prevention ICD had a history of clinical heart failure (80.4%), NYHA class II-III symptoms (77.1%) and LVEF ≤35% (96.9%). In the secondary prevention ICD cohort, 88.4% were for sustained ventricular tachycardia or survived cardiac arrest from ventricular arrhythmia. Compared to primary prevention CRT Defibrillators (n = 155), those receiving CRT Pacemakers (n = 175) were older (median age 74 vs 66 years) and more likely to be female (38.3% vs 19.4%). Of the 427 (27.0%) ICD replacements (mean duration 6.3 years), 46.6% had received appropriate device therapy while 17.8% received inappropriate therapy. The ICD implant rate was 119 per million population with regional variation in implant rates, ratio of primary prevention ICD implants, and selection of CRT modality. CONCLUSION: In contemporary NZ practice three-quarters of ICD implants were new implants, of which half were for primary prevention. The majority met current guideline indications. Patients receiving CRT pacemaker were older and more likely to be female.

Early direct current cardioversion or ablation for atrial fibrillation or atrial flutter and acute decompensated heart failure.

AIMS: Guidelines recommend initial rate control in haemodynamically stable patients with atrial fibrillation (AF) or atrial flutter (AFL) and acute decompensated heart failure (ADHF). There is limited data on early inpatient rhythm control. We investigated the outcomes of patients managed with early TOE-guided DC cardioversion (DCCV) or ablation. METHODS: We retrospectively analysed patients admitted to a single centre with AF or AFL and ADHF with LVEF≤40% that underwent inpatient TOE-guided DCCV or ablation. The primary endpoint was the one year composite outcome of mortality or rehospitalisation for heart failure. RESULTS: We identified 79 patients, including 33 with AF (32 DCCV, one ablation) and 46 with AFL (22 DCCV, 24 ablation). The primary endpoint occurred in 20%. One-year mortality was 2.5%. There were significantly fewer rehospitalisations for arrhythmia or heart failure with AFL-ablation compared to AFL-DCCV (21% vs 64%, p=<0.01). Clinical recurrence of AF or AFL was 43%. At follow-up LV assessment, LVEF>40% was found in 75% (p=<0.01), including 87% of patients without known cardiomyopathy and 82% of patients in sinus rhythm. CONCLUSION: Early inpatient DCCV or ablation for AF or AFL and ADHF had low mortality rates and rehospitalisation for heart failure with substantial improvement in LV function at follow-up.

Comparison of contemporary risk scores for predicting outcomes after surgery for active infective endocarditis.

Decision making regarding surgery for acute bacterial endocarditis is complex given its heterogeneity and often fatal course. Few studies have investigated the utility of operative risk scores in this setting. Endocarditis-specific scores have recently been developed. We assessed the prognostic utility of contemporary risk scores for mortality and morbidity after endocarditis surgery. Additive and logistic EuroSCORE I, EuroSCORE II, additive Society of Thoracic Surgeon's (STS) Endocarditis Score and additive De Feo-Cotrufo Score were retrospectively calculated for patients undergoing surgery for endocarditis during 2005-2011. Pre-specified primary outcomes were operative mortality, composite morbidity and mortality during follow-up. A total of 146 patients were included with an operative mortality of 6.8 % followed for 4.1 ± 2.4 years. Mean scores were additive EuroSCORE I: 8.0 ± 2.5, logistic EuroSCORE I: 13.2 ± 10.1 %, EuroSCORE II: 9.1 % ± 9.4 %, STS Score: 32.2 ± 13.5 and De Feo-Cotrufo Score: 14.6 ± 9.2. Corresponding areas under curve (AUC) for operative mortality 0.653, 0.645, 0.656, 0.699 and 0.744; for composite morbidity were 0.623, 0.625, 0.720, 0.714 and 0.774; and long-term mortality 0.588, 0.579, 0.686, 0.735 and 0.751. The best tool for post-operative stroke was EuroSCORE II: AUC 0.837; for ventilation >24 h and return to theatre the De Feo-Cotrufo Scores were: AUC 0.821 and 0.712. Pre-operative inotrope or intra-aortic balloon pump treatment, previous coronary bypass grafting and dialysis were independent predictors of operative and long-term mortality. In conclusion, risk models developed specifically from endocarditis surgeries and incorporating endocarditis variables have improved prognostic ability of outcomes, and can play an important role in the decision making towards surgery for endocarditis.

Valvular repair or replacement for mitral endocarditis: 7-year cohort study.

BACKGROUND: A few studies have compared mitral valve repair and replacement in the setting of infective endocarditis, with varying results. We compared the characteristics and outcomes of mitral repair and replacement in endocarditis patients. METHODS: All patients undergoing mitral valve repair or replacement for active mitral endocarditis during 2005-2011 were included. Operative and follow-up mortality, composite morbidity, recurrent endocarditis, and redo operations were prespecified endpoints for analyses. RESULTS: There were 25 and 35 patients undergoing mitral valve repair and replacement, respectively. They were followed-up for 3.9 ± 2.5 years. Valve replacement patients were older (p = 0.029), had a higher prevalence of intracardiac abscess (p = 0.035), previous endocarditis (p = 0.036), atrial fibrillation (p = 0.001), worse renal function (p = 0.013), higher risk scores (p = 0.004-0.020), and longer operation times (p < 0.001). Repair and replacement had similar rates of operative mortality (4.0% vs. 8.6%, p = 0.634), composite morbidity (16.0% vs. 28.6%, p = 0.357), survival (p = 0.564), recurrent endocarditis (p = 0.081), and redo operations (p = 0.813). Independent predictors of operative mortality were preoperative inotropic or intraaortic balloon pump support. The independent predictor of mortality during follow-up was dialysis. Independent predictors of composite morbidity were intracardiac abscess and hypercholesterolemia. The independent predictor of recurrent endocarditis was previous endocarditis, and the independent predictor of redo operation was previous stroke. CONCLUSION: Mitral valve replacement candidates had more baseline risk factors and higher raw rates of postoperative mortality and morbidity, which did not reach statistical significance.

Characteristics and outcomes for right heart endocarditis: six-year cohort study.

Right heart endocarditis makes up 5-10% of all infective endocarditis involving valvular, congenital and artificial structures. Given the limited literature in this area, we reviewed the characteristics, management and outcomes of this condition in this retrospective cohort study. Thirty-five patients with right heart endocarditis admitted to Auckland City Hospital during 2005-2010 were followed-up for 3.4+/-2.5 years. In-hospital mortality was 11.4% (4), all occurring in those treated medically (20.0% (4) vs 0.0% (0), P=0.119). Surgical intervention was independently associated with reduced long-term mortality (HR 0.078, 95%CI 0.010-0.609, P=0.015) in multivariate analysis, while concurrent left heart endocarditis predicted both in-hospital mortality (HR 11.0, 95%CI 1.18-102, P=0.027) and long-term mortality (HR 3.20, 95%CI 1.03-9.92, P=0.044). Our study showed that surgical intervention and concomitant left heart endocarditis are positive and negative prognostic factors for outcomes after right heart endocarditis.

Frequency and sequelae of retained implanted cardiac device material post heart transplantation.

BACKGROUND: Cardiac implantable electronic devices (CIEDs) have now become common therapeutic adjuncts for patients prior to orthotopic heart transplantation (OHT). Removal of the generator and the intracardiac components occurs at time of transplantation but removal of the intravascular portion of leads may be unsuccessful without specialized extraction equipment. METHODS: We performed a retrospective audit of chest radiographs and clinical records of patients undergoing OHT at Green Lane and Auckland City Hospitals between 2002 and 2012. RESULTS: At the time of transplant surgery, 56 of 100 patients had a CIED in situ. Hardware was retained postoperatively in 22 (39%), and the CIED had been in situ for 47 (interquartile range [IQR] 16-68) months for these cases, compared to 14 (IQR 3-24) months in those without. In two (9%) patients, the device generator was electively explanted during the week following OHT. There were no subsequent procedures undertaken to remove retained lead fragments. One (4%) had lead fragment embolization, one (4%) had endoluminal fragment migration, and one (4%) had lead fragment erosion into the mediastinum; all were asymptomatic and without adverse clinical sequelae. There was no infection associated with this hardware. The presence of retained lead fragments was not associated with additional mortality. CONCLUSIONS: Retained lead fragments following OHT occur commonly, without adverse clinical events for this cohort; however, the long-term clinical implications remain uncertain. Complete removal of all CIED hardware should be attempted at the time of OHT, and when this is not possible leads should be left in a state that facilitates their removal at a later date if required.

How long do acute coronary syndrome patients wait for reperfusion, diagnostic coronary angiography and surgical revascularisation?

AIM: To describe the components of in-hospital waiting time to investigation and management in patients with acute coronary syndromes (ACS) admitted to the Middlemore Hospital (MMH) Coronary Care Unit. METHOD: We examined the time to (1) reperfusion therapy in ST-elevation myocardial infarction (STEMI), (2) coronary angiography in ACS, and (3) surgical revascularisation. Data was collected prospectively for consecutive patients via the Acute PREDICT ACS registry. RESULTS: Of 280 STEMI admissions in 2009 and 2010, 101 underwent primary percutaneous coronary intervention. The median door-to-balloon time when performed on site at MMH was 83 minutes (IQR 69-101 minutes) compared with 135 minutes (IQR 112-165 minutes) for those transferred after hours to Auckland City Hospital (ACH). Of 2115 ACS admissions between 2007 and 2010 84% underwent inpatient coronary angiography and 69% of these underwent this within 3 days. The strongest predictors of a >3 day delay were advanced chronic kidney disease (odds ratio 3.68, 95% CI 2.08-6.51) and presenting late in the week (odds ratio 2.85, 95% CI 2.30-3.54). 329 patients (16%) underwent coronary artery bypass graft surgery (CABG). The median time from admission to inpatient CABG was 13 days and from discharge to outpatient CABG was 155 days. Of ACS patients referred for outpatient surgery in the public sector 38% were readmitted with further ACS whilst waiting. CONCLUSION: Important delays were identified across the spectrum of post-admission care for ACS patients potentially impacting on both patient outcomes and the cost of care. Active quality improvement programmes to reduce delays are required.

Pharmacogenetic testing for clopidogrel using the rapid INFINITI analyzer: a dose-escalation study.

OBJECTIVES: Our aim was to assess whether a higher clopidogrel maintenance dose has a greater antiplatelet effect in CYP2C19*2 allele carriers compared with noncarriers. BACKGROUND: Clopidogrel is a prodrug that is biotransformed by the cytochrome P450 enzymes CYP2C19, 2C9, and 3A4, 2B6, 1A2. The CYPC219*2 loss of function variant has been associated with a reduced antiplatelet response to clopidogrel and a 3-fold risk of stent thrombosis. METHODS: Forty patients on standard maintenance dosage clopidogrel (75 mg), for 9.4 +/- 9.2 weeks, were enrolled into a dose escalation study. Platelet function was assessed at baseline and after 1 week of 150 mg once daily using the VerifyNow platelet function analyzer (Accumetrics Ltd., San Diego, California). Genomic DNA was hybridized to a BioFilmChip microarray on the INFINITI analyzer (AutoGenomics Inc., Carlsbad, California) and analyzed for the CYP19*2, *4, *17, and CYP2C9*2, *3 polymorphisms. RESULTS: Platelet inhibition increased over 1 week, mean +8.6 +/- 13.5% (p = 0.0003). Carriers of the CYP2C19*2 allele had significantly reduced platelet inhibition at baseline (median 18%, range 0% to 72%) compared with wildtype (wt) (median 59%, range 11% to 95%, p = 0.01) and at 1 week (p = 0.03). CYP2C19*2 allele carriers had an increase in platelet inhibition of (mean +9 +/- 11%, p = 0.03) and reduction in platelet reactivity (mean -26 +/- 38 platelet response unit, p = 0.04) with a higher dose. Together CYP2C19*2 and CYP2C9*3 loss of function carriers had a greater change in platelet inhibition with 150 mg daily than wt/wt (+10.9% vs. +0.7%, p = 0.04). CONCLUSIONS: Increasing the dose of clopidogrel in patients with nonresponder polymorphisms can increase antiplatelet response. Personalizing clopidogrel dosing using pharmacogenomics may be an effective method of optimizing treatment.

Digital implantable loop recorders in the investigation of syncope in children: benefits and limitations.

BACKGROUND: Conventional diagnostic methods for detecting arrhythmogenic causes of syncope in children are poor. Digital implantable loop recorders are of proven value in adults. OBJECTIVES: The purpose of this study was to evaluate digital implantable loop recorders in the investigation of syncope in children. METHODS: We reviewed the clinical and technical records of 18 consecutive patients (6 female and 12 male; age