Macrophages in cardiac remodelling after myocardial infarction.

Myocardial infarction (MI), as a result of thrombosis or vascular occlusion, is the most prevalent cause of morbidity and mortality among all cardiovascular diseases. The devastating consequences of MI are compounded by the complexities of cellular functions involved in the initiation and resolution of early-onset inflammation and the longer-term effects related to scar formation. The resultant tissue damage can occur as early as 1 h after MI and activates inflammatory signalling pathways to elicit an immune response. Macrophages are one of the most active cell types during all stages after MI, including the cardioprotective, inflammatory and tissue repair phases. In this Review, we describe the phenotypes of cardiac macrophage involved in MI and their cardioprotective functions. A specific subset of macrophages called resident cardiac macrophages (RCMs) are derived from yolk sac progenitor cells and are maintained as a self-renewing population, although their numbers decrease with age. We explore sophisticated sequencing techniques that demonstrate the cardioprotective properties of this cardiac macrophage phenotype. Furthermore, we discuss the interactions between cardiac macrophages and other important cell types involved in the pathology and resolution of inflammation after MI. We summarize new and promising therapeutic approaches that target macrophage-mediated inflammation and the cardioprotective properties of RCMs after MI. Finally, we discuss future directions for the study of RCMs in MI and cardiovascular health in general.

Assessing the Impact of Transcatheter Aortic Valve Implantation on Cardiac Catheterisation: A Multicentric Study.

BACKGROUND: The success rate of coronary angiography (CA) after transcatheter aortic valve implantation (TAVI) is variable. Our aim was to investigate CA difficulty, outcomes, and predictors of difficult CA after TAVI. METHOD: This was an international multicentric retrospective cohort study that included patients with TAVI and subsequent CA between January 2010 and December 2019. Difficulty with CA was graded as 1 (normal), 2 (partial engagement, complete vessel opacification), 3 (partial engagement, incomplete vessel opacification), and 4 (unsuccessful angiography). Patients were grouped as (a) "easy" (grade 1 for left and right) or (b) "difficult" (grade >1 for either). We compared baseline characteristics and outcomes, and performed multivariate logistic regression for predictors of difficult CA. RESULTS: Of 96 patients included (mean age 77.4±8.7 years, 48 [50%] male), 88 (92%) had successful CA. Right CA was successful in 80 (83%) patients and left CA in 91 (95%) (p<0.0001). The "difficult" group (n=41 [43%]) had higher Society of Thoracic Surgery (STS) scores (7.6±4.9 vs 5.4±4.0; p=0.022), smaller annulus perimeters (72.4±5.4 mm vs 76.2±9.4 mm; p=0.049), greater use of self-expanding valves (83% vs 18%; p<0.0001), increased valve size (26.8±2.1 mm vs 25.6±3.0 mm; p=0.032), and increased oversizing for area (44.3%±17.4% vs 23.6%±22.0%; p=0.0002) and perimeter (17.5%±8.2% vs 7.1%±10.8%; p<0.0001). There was no difference in outcomes except for increased major bleeding (7.3% vs 0.0%; p=0.042). The strongest predictor for "difficult" CA was self-expanding valves when compared to balloon-expandable valves (adjusted odds ratio [aOR], 15.23; 95% confidence interval [CI], 2.27-102.40). Society of Thoracic Surgery score was borderline predictive (aOR, 1.26; 95% CI, 1.04-1.52). CONCLUSIONS: Our results show that after TAVI, CA success rate is high, right CA is more difficult than left, self-expanding valves predispose to difficult CA, and STS score weakly predicts difficult CA. This study is hypothesis-generating and more research is required to confirm these findings.

Predicting Coronary Artery Disease in Primary Care: Development and Validation of a Diagnostic Risk Score for Major Ethnic Groups in Southeast Asia.

BACKGROUND: Coronary artery disease (CAD) risk prediction tools are useful decision supports. Their clinical impact has not been evaluated amongst Asians in primary care. OBJECTIVE: We aimed to develop and validate a diagnostic prediction model for CAD in Southeast Asians by comparing it against three existing tools. DESIGN: We prospectively recruited patients presenting to primary care for chest pain between July 2013 and December 2016. CAD was diagnosed at tertiary institution and adjudicated. A logistic regression model was built, with validation by resampling. We validated the Duke Clinical Score (DCS), CAD Consortium Score (CCS), and Marburg Heart Score (MHS). MAIN MEASURES: Discrimination and calibration quantify model performance, while net reclassification improvement and net benefit provide clinical insights. KEY RESULTS: CAD prevalence was 9.5% (158 of 1658 patients). Our model included age, gender, type 2 diabetes mellitus, hypertension, smoking, chest pain type, neck radiation, Q waves, and ST-T changes. The C-statistic was 0.808 (95% CI 0.776-0.840) and 0.815 (95% CI 0.782-0.847), for model without and with ECG respectively. C-statistics for DCS, CCS-basic, CCS-clinical, and MHS were 0.795 (95% CI 0.759-0.831), 0.756 (95% CI 0.717-0.794), 0.787 (95% CI 0.752-0.823), and 0.661 (95% CI 0.621-0.701). Our model (with ECG) correctly reclassified 100% of patients when compared with DCS and CCS-clinical respectively. At 5% threshold probability, the net benefit for our model (with ECG) was 0.063. The net benefit for DCS, CCS-basic, and CCS-clinical was 0.056, 0.060, and 0.065. CONCLUSIONS: PRECISE (Predictive Risk scorE for CAD In Southeast Asians with chEst pain) performs well and demonstrates utility as a clinical decision support for diagnosing CAD among Southeast Asians.

Atrial Fibrillation and the Prognostic Performance of Biomarkers in Heart Failure.

BACKGROUND: Consideration of circulating biomarkers for risk stratification in heart failure (HF) is recommended, but the influence of atrial fibrillation (AF) on prognostic performance of many markers is unclear. We investigated the influence of AF on the prognostic performance of circulating biomarkers in HF. METHODS: N-terminal pro-B-type natriuretic peptide (NT-proBNP), mid-regional-pro-atrial natriuretic peptide, C-type natriuretic peptide (CNP), NT-proCNP, high-sensitivity troponin-T, high-sensitivity troponin-I, mid-regional-propeptide adrenomedullin, co-peptin, growth differentiation factor-15, soluble Suppressor of Tumorigenicitiy (sST2), galectin-3, and procalcitonin plasma concentrations were measured in a prospective, multicenter study of adults with HF. AF was defined as a previous history of AF, and/or presence of AF/flutter on baseline 12-lead electrocardiogram. The primary outcome was the composite of HF-hospitalization or all-cause mortality at 2 years. RESULTS: Among 1099 patients (age 62 ± 12years, 28% female), 261(24%) patients had AF. Above-median concentrations of all biomarkers were independently associated with increased risk of the primary outcome. Significant interactions with AF were detected for galectin-3 and sST2. In considering NT-proBNP for additive risk stratification, sST2 (adjusted hazard ratio [AHR]1.85, 95%confidence interval [C.I.] 1.17-2.91) and galectin-3 (AHR1.85, 95%C.I. 1.09-2.45) were independently associated with increased primary outcome only in the presence of AF. The prognostic performance of sST2 was also stronger in AF for all-cause mortality (AF: AHR2.82, 95%C.I. 1.26-6.21; non-AF: AHR1.78, 95% C.I. 1.14-2.76 without AF), while galectin-3 predicted HF-hospitalization only in AF (AHR1.64, 95%C.I. 1.03-2.62). CONCLUSIONS: AF modified the prognostic utility of selected guideline-endorsed HF-biomarkers. Application of markers for prognostic purposes in HF requires consideration of the presence or absence of AF. CLINICAL TRIAL REGISTRATION: ACTRN12610000374066.

Transjugular mitral valve repair with the MitraClip: A step-by-step guide.

The MitraClip procedure is carried out almost exclusively via the transfemoral approach. However, in some patients transfemoral delivery of MitraClip is not technically feasible (e.g., occluded inferior vena cava or tortuous/obstructive iliofemoral venous anatomy). The technical considerations and challenges of the MitraClip procedure are amplified when an alternate route is considered. We describe a successful case of MitraClip performed via the right internal jugular (IJ) approach in a patient with a flail A3 scallop and previous mitral valve repair. We reviewed prior cases in the literature and discuss step-by-step the pertinent clinical and technical considerations for performing this procedure via the transjugular route. In summary, the right IJ access site provides a reasonable alternative to perform the MitraClip procedure in cases where femoral access is contraindicated or prohibitive. A thorough understanding of the technical considerations is crucial in improving procedural success rates.

Mortality and hospitalization outcomes of interstitial lung disease and pulmonary hypertension in the Singapore systemic sclerosis cohort.

OBJECTIVES: We compared mortality and hospitalization rates in four groups of patients with systemic sclerosis (SSc) [isolated pulmonary arterial hypertension (PAH) or interstitial lung disease (ILD), concomitant ILD-pulmonary hypertension (PH), and no/mild pulmonary involvement]. METHODS: In the Systemic Sclerosis Cohort Singapore (SCORE), ILD was diagnosed by HRCT and significant ILD was defined by forced vital capacity <70% predicted. Patients were classified as PAH if echocardiographic systolic pulmonary artery pressure (sPAP) ≥50 mmHg or right heart catheterization (RHC) mean PAP ≥25 mmHg. Multivariable regression analyses were performed to determine factors associated with mortality and hospital admissions per year. Cox proportional hazard model was used to analyze survival. RESULTS: Of 490 SSc patients, 50 patients had PAH, 92 patients had ILD and 43 patients had ILD-PH. Of 93 patients with PAH or ILD-PH, 56 were based on echocardiography and 37 on RHC. Patients with ILD-PH (HR 3.77, 95% CI: 2.05-6.93) had the highest risk of death, followed by PAH (HR 3.03, 95% CI: 1.60-5.76) and ILD (HR 1.84, 95% CI: 1.04-3.28). After adjustment for confounders, PAH (HR 2.39, 95% CI: 1.13-5.07) remained independently associated with mortality, but not ILD-PH or ILD. Other factors associated with mortality were male gender, age at SSc diagnosis, malabsorption and digital ulcer/ gangrene. Increased hospitalization rate was associated with renal crisis, right heart failure and PAH medications, but not SSc groups. CONCLUSION: PAH is an independent risk factor of mortality in SSc. Increased hospitalization rate was not associated with SSc groups. Other factors associated with increased mortality and hospital admissions were identified.

Harnessing technology and molecular analysis to understand the development of cardiovascular diseases in Asia: a prospective cohort study (SingHEART).

BACKGROUND: Cardiovascular disease (CVD) imposes much mortality and morbidity worldwide. The use of "deep learning", advancements in genomics, metabolomics, proteomics and devices like wearables have the potential to unearth new insights in the field of cardiology. Currently, in Asia, there are no studies that combine the use of conventional clinical information with these advanced technologies. We aim to harness these new technologies to understand the development of cardiovascular disease in Asia. METHODS: Singapore is a multi-ethnic country in Asia with well-represented diverse ethnicities including Chinese, Malays and Indians. The SingHEART study is the first technology driven multi-ethnic prospective population-based study of healthy Asians. Healthy male and female subjects aged 21-69 years old without any prior cardiovascular disease or diabetes mellitus will be recruited from the general population. All subjects are consented to undergo a detailed on-line questionnaire, basic blood investigations, resting and continuous electrocardiogram and blood pressure monitoring, activity and sleep tracking, calcium score, cardiac magnetic resonance imaging, whole genome sequencing and lipidomic analysis. Outcomes studied will include mortality and cause of mortality, myocardial infarction, stroke, malignancy, heart failure, and the development of co-morbidities. DISCUSSION: An initial target of 2500 patients has been set. From October 2015 to May 2017, an initial 683 subjects have been recruited and have completed the initial work-up the SingHEART project is the first contemporary population-based study in Asia that will include whole genome sequencing and deep phenotyping: including advanced imaging and wearable data, to better understand the development of cardiovascular disease across different ethnic groups in Asia.

Can Lightning Strike Twice? Tackling Complications From Transcatheter Aortic Valve Implantation.

TAVI complications may occur in the peri- and postprocedural periods. A 79-year-old woman with known severe degenerative calcified aortic stenosis underwent transfemoral TAVI; prior to groin closure, she became hypotensive. Prosthetic valve thrombosis was confirmed with transesophageal echocardiography and computed tomography aortogram, which showed thrombus on the immobile non-coronary cusp leaflet.

Ultramorphological analysis of plaque advancement and cholesterol crystal formation in Ldlr knockout mouse atherosclerosis.

BACKGOUND AND AIMS: The low-density lipoprotein receptor-deficient (Ldlr-/-) mouse has been utilized by cardiovascular researchers for more than two decades to study atherosclerosis. However, there has not yet been a systematic effort to document the ultrastructural changes that accompany the progression of atherosclerotic plaque in this model. METHODS: Employing several different staining and microscopic techniques, including immunohistochemistry, as well as electron and polarized microscopy, we analyzed atherosclerotic lesion development in Ldlr-/- mice fed an atherogenic diet over time. RESULTS: Lipid-like deposits occurred in the subendothelial space after only one week of atherogenic diet. At two weeks, cholesterol crystals (CC) formed and increased thereafter. Lipid, CC, vascular smooth muscles cells, and collagen progressively increased over time, while after 4 weeks, relative macrophage content decreased. Accelerated accumulation of plate- and needle-shaped CC accompanied plaque core necrosis. Lastly, CC were surrounded by cholesterol microdomains, which co-localized with CC through all stages of atherosclerosis, indicating that the cholesterol microdomains may be a source of CC. CONCLUSIONS: Here, we have documented, for the first time in a comprehensive way, atherosclerotic plaque morphology and composition from early to advanced stages in the Ldlr-/- mouse, one of the most commonly used animal models utilized in atherosclerosis research.

Role of Macrophages in Cardioprotection.

Cardiovascular diseases are the leading cause of mortality worldwide. It is widely known that non-resolving inflammation results in atherosclerotic conditions, which are responsible for a host of downstream pathologies including thrombosis, myocardial infarction (MI), and neurovascular events. Macrophages, as part of the innate immune response, are among the most important cell types in every stage of atherosclerosis. In this review we discuss the principles governing macrophage function in the healthy and infarcted heart. More specifically, how cardiac macrophages participate in myocardial infarction as well as cardiac repair and remodeling. The intricate balance between phenotypically heterogeneous populations of macrophages in the heart have profound and highly orchestrated effects during different phases of myocardial infarction. In the early "inflammatory" stage of MI, resident cardiac macrophages are replaced by classically activated macrophages derived from the bone marrow and spleen. And while the macrophage population shifts towards an alternatively activated phenotype, the inflammatory response subsides giving way to the "reparative/proliferative" phase. Lastly, we describe the therapeutic potential of cardiac macrophages in the context of cell-mediated cardio-protection. Promising results demonstrate innovative concepts; one employing a subset of yolk sac-derived, cardiac macrophages that have complete restorative capacity in the injured myocardium of neonatal mice, and in another example, post-conditioning of cardiac macrophages with cardiosphere-derived cells significantly improved patient's post-MI diagnoses.

Potential role of IL-37 in atherosclerosis.

IL-37 is a member of the IL-1 family, but unlike most other members of this family of cytokines, it has wide-ranging anti-inflammatory properties. Initially shown to bind IL-18 binding protein and prevent IL-18-mediated inflammation, its known role has been expanded to include distinct pathways, both intracellular involving the transcription factor Smad3, and extracellular via binding to the orphan receptor IL-1R8. A number of recent publications investigating the role of IL-37 in atherosclerosis and ischemic heart disease have revealed promising therapeutic value of the cytokine. Although research concerning the role of IL-37 and its mechanism in atherosclerosis is relatively scant, there are a number of well-known atherosclerotic processes that this cytokine can mediate with the potential of modulating the disease progression itself. This review will probe in detail the effects of IL-37 on important pathological processes such as inflammation, dysregulated lipid metabolism, and apoptosis, by analyzing existing data as well as exploring the potential of this cytokine to influence these properties.

Is there a role for remote ischemic conditioning in preventing 5-fluorouracil-induced coronary vasospasm?

Cardiac ischemia associated with chemotherapy has been linked to several anti-neoplastic agents and is multifactorial in etiology. Coronary artery vasospasm is one of the most commonly reported effects of cancer therapy that can lead to myocardial ischemia or infarction. The chemotherapy agent 5-fluorouracil (5-FU) or its oral pro-drug capecitabine can result in coronary vascular endothelial dysfunction causing coronary artery spasm, and possibly coronary thrombosis. These drugs have also been shown to be associated with myocardial infarction, malignant ventricular arrhythmias, heart failure, cardiogenic shock, and sudden death. The proposed mechanisms underlying cardiotoxicity induced by 5-FU are vascular endothelial damage followed by thrombus formation, ischemia secondary to coronary artery vasospasm, direct toxicity on myocardium, and thrombogenicity. There remains a pressing need to discover novel and effective therapies that can prevent or ameliorate 5-FU associated cardiotoxicity. To this point, promising overlap has been observed between proposed remote ischemic conditioning (RIC) cardioprotective mechanisms and 5FU-associated cardiotoxic cellular pathways. RIC, in which transient episodes of limb ischemia and reperfusion (induced by inflations and deflations of a pneumatic cuff placed on the upper arm or thigh), confer both cardioprotective and vasculoprotective effects, and may therefore prevent 5-FU coronary artery spasm/cardiotoxicity. In this review, we will be discussing the following potentially therapeutic aspects of RIC in ameliorating 5-FU associated cardiotoxicity: sequential phases of 5-FU cardiotoxicity as possible targets for dual windows of cardioprotection characteristic of RIC; protective effects of RIC on endothelial function and microvasculature in relation to 5-FU induced endothelial dysfunction/microvascular dysfunction; reduction in platelet activation by RIC in the context of 5-FU induced thrombogenicity; and the utility of improvement in mitochondrial function conferred by RIC in 5-FU induced cellular toxicity secondary to mitochondrial dysfunction.

Outcomes of primary percutaneous coronary intervention in acute myocardial infarction due to unprotected left main thrombosis: The Asia-Pacific Left Main ST-Elevation Registry (ASTER).

INTRODUCTION: Prior studies of ULM STEMI have been confined to small cohorts. Recent registry data with larger patient cohorts have shown contrasting results. We aim to study the outcomes of patients with unprotected left main (ULM) ST-elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI). METHODS: The Asia-pacific left main ST-Elevation Registry (ASTER) is a multicenter retrospective registry involving 4 sites in Singapore, South Korea, and the United States. The registry included patients presenting with STEMI due to an ULM coronary artery culprit lesion who underwent emergency PCI. The primary outcome was in-hospital mortality. Secondary outcomes included major adverse cardiovascular events. RESULTS: A total of 67 patients (mean age 64.2 ± 12.8 years, 53 [79.1%] males) were included. The distal left main bifurcation was most commonly involved (85%, n = 57). Fifty one (76%) patients had TIMI 3 flow post-PCI. The in-hospital mortality rate was 47.8% (n = 32); 61% (n = 41) had cardiac failure, 4% (n = 3) had emergency coronary artery bypass grafting, 1% (n = 1) had a re-infarction, 3% (n = 2) had stroke and 55% (n = 37) had malignant ventricular arrhythmias. On multivariate analysis, predictors of in-hospital mortality included older age (odds ratio (OR) 1.085 (95% confidence interval (CI) 1.002-1.175), P = 0.044), diabetes mellitus (OR 10.882 (95%CI 11.074-110.287), P = 0.043) and absence of post-PCI TIMI 3 flow (OR 71.429 (95%CI 2.985-1000), P = 0.008). CONCLUSIONS: STEMI from culprit unprotected left main coronary artery stenosis is associated with significant mortality and morbidity. Emergency PCI provides an important treatment option in this high-risk group, but in-hospital mortality remains high.

Clinical Outcomes of Bioresorbable Scaffold in Coronary Artery Disease: A Systematic Literature Review.

OBJECTIVES: We aim to perform a systematic literature review on all studies reporting the clinical outcomes of the use of bioresorbable scaffolds (BRS) in different settings of coronary artery disease (CAD). BACKGROUND: BRS are designed to provide early support of the vessel wall postangioplasty, deliver antiproliferative agents to prevent excessive hyperplastic healing responses and finally "disappear" when no longer required. Emerging data have provided evidence of their use in specific clinical scenarios. METHODS: A comprehensive literature search was performed by 2 independent reviewers utilizing MEDLINE, EMBASE, and Cochrane Library databases. The only 2 CE marked BRS: everolimus-eluting Bioresorbable vascular scaffold ABSORB BVS and the myolimus-eluting DESolve Bioresorbable Coronary Scaffold (BCS) System were included. RESULTS: The studies were categorized into: ST elevation myocardial infarction (STEMI), stable CAD, and "all-comers" group. Thirty-one studies were included; 8 in STEMI patients (all ABSORB), 15 in stable CAD patients. In the STEMI group (n = 606), acute procedural success ranged from 96% to 100%, cardiac mortality 0-9.1%, recurrent MI and stent thrombosis rates were 0-4.3%. In the stable CAD group, the 13 ABSORB studies (n = 3259) demonstrated cardiac mortality rate of 0-0.6%, recurrent MI rate 0-4.5%, and stent thrombosis rate 0-4.3% CONCLUSIONS: Current clinical data suggest the BRS, especially the ABSORB BVS, may represent a reasonable alternative to DES in uncomplicated coronary anatomy.

Poly(lactide-co-glycolide) microspheres for MRI-monitored delivery of sorafenib in a rabbit VX2 model.

Transcatheter arterial embolization and chemoembolization are standard locoregional therapies for hepatocellular carcinoma (HCC). However, these can result in tumor hypoxia, thus promoting tumor angiogenesis. The anti-angiogenic agent sorafenib is hypothesized to improve outcomes; however, oral administration limits patient tolerance. Therefore, the purpose of this study was to fabricate poly(lactide-co-glycolide) microspheres for local sorafenib delivery to tumors during liver-directed embolotherapies. Iron oxide nanoparticles (IONP) were co-encapsulated for magnetic resonance imaging (MRI) of microsphere delivery. Microspheres were fabricated using a double emulsion/solvent evaporation method and characterized for size, sorafenib and IONP content, and MRI properties. MRI was performed before and after intra-arterial microsphere infusions in a rabbit VX2 liver tumor model. The microspheres were 13 microns in diameter with 8.8% and 0.89% (w/w) sorafenib and IONP, respectively. 21% and 28% of the loaded sorafenib and IONP, respectively, released within 72 h. Rabbit VX2 studies demonstrated that sorafenib microspheres normalized VEGFR 2 activity and decreased microvessel density. Quantitative MRI enabled in vivo visualization of intra-hepatic microsphere distributions. These methods should avoid systemic toxicities, with MRI permitting follow-up confirmation of microsphere delivery to the targeted liver tumors.

Predictors of two-year mortality in Asian patients with heart failure and preserved ejection fraction.

INTRODUCTION: Mortality in patients with heart failure and preserved ejection fraction (HFpEF) remains high. Data from Asia is lacking. We aim to study the impact of ethnicity and other predictors of mortality in patients admitted for HFpEF in a multi-ethnic Asian country. MATERIAL AND METHODS: Consecutive patients admitted to two local institutions with heart failure and ejection fraction ≥50% on transthoracic echocardiogram from Jan 2008 to Dec 2009 were included. All patients were followed-up for 2 years. Overall mortality was obtained from the national registry of deaths in our country. RESULTS: A total of 1960 patients with heart failure were included. 751 (38.3%) patients had HFpEF. Overall mortality at two years was 26.6% (n=200) compared to 37.1% (n=449) in patients with reduced ejection fraction (HR 0.618 (95% CI 0.508-0.753), p<0.001). Ethnicity did not predict mortality. On multivariable Cox regression analysis, significant predictors of two-year mortality in HFpEF patients were older age (HR 1.027 (1.011-1.044)), prior myocardial infarction (HR 1.577 (1.104-2.253)), prior stroke (HR 1.475 (1.055-2.061)), smoking (HR 1.467 (1.085-1.985)), higher creatinine levels (HR 1.002 (1.001-1.003)) and use of mineralocorticoid receptor antagonists (HR 1.884 (1.226-2.896)). Use of warfarin (HR 0.506 (0.304-0.842)) and statins (HR 0.585 (0.435-0.785)) were associated with significantly lower mortality. CONCLUSIONS: In our Asian population presenting with HFpEF, two-year mortality was 26.6%. Ethnicity did not predict mortality. Older age, prior myocardial infarction, prior stroke, smoking, and higher creatinine levels were found to be significant predictors of mortality.

Percutaneous mitral valve repair with the MitraClip: early results from the MitraClip Asia-Pacific Registry (MARS).

AIMS: Percutaneous MitraClip therapy has been shown to be safe and efficacious in mitral regurgitation (MR). Our aim was to describe early outcomes in patients from the Asia- Pacific region. METHODS AND RESULTS: The MitraClip Asia-Pacific Registry (MARS) includes data from eight different centres in five countries in the Asia-Pacific region. The primary efficacy outcome was reduction in MR to ≤2+ at 30 days. The safety outcome was 30-day freedom from major adverse events (MAE), defined as the composite of death, myocardial infarction, non-elective cardiac surgery, renal failure, transfusion of ≥2 units of blood, ventilation for >48 hours, septicaemia, and new onset atrial fibrillation. A total of 142 patients underwent the MitraClip procedure from February 2011 to October 2013. Fifty-three point five percent (76) of patients had functional MR, 45.8% (65) had degenerative MR and 0.7% (1) had mixed MR. The acute procedural success rate was 93.7% (133). Thirty-one point seven percent of the patients were in NYHA Class I-II at baseline, compared to 82.1% at 30 days (p<0.001). Zero percent (0) of the patients had ≤2+ MR at baseline compared to 76.8% (109) at 30 days (p<0.001). CONCLUSIONS: Results from the Asia-Pacific region show that the MitraClip procedure is effective in reducing mitral regurgitation and has favourable short-term safety outcomes.

Catheter ablation of ventricular fibrillation storm in a long QT syndrome genotype carrier with normal QT interval.

Patients with long QT syndrome can sometimes present with a ventricular fibrillation (VF) storm. Catheter ablation of culprit premature ventricular complexes responsible for the triggering of the VF episodes may be required in rare cases of electrical storm that do not respond to conventional measures, and this can be life-saving. We describe a case of emergency catheter ablation in a young woman with a normal corrected QT interval, who presented with malignant VF storm for the first time. We also discuss the diagnostic and management challenges involved, as well as the value of genetic testing in refining the diagnosis.