Common Designs of Custom-Made Fenestrated Arch Devices and Applicability of an Off-the-Shelf Design.

OBJECTIVES: To analyze device designs, similarities and overlaps of custom-made fenestrated arch endografts intended for mid/distal arch thoracic endovascular aortic repair. MATERIALS AND METHODS: A multicenter cross-sectional study analyzing custom-made anonymized graft plans was performed. Graft plans were included from a cohort of mid/distal aortic arch repairs using custom-made fenestrated aortic endografts treated at 8 centers. Grafts targeting >2 arteries were excluded. No patient/clinical data were analyzed. A descriptive analysis was performed followed by an analysis of overlap of the designs to reach a common design in which the greatest number of grafts would overlap. RESULTS: One hundred thirty-one graft plans were included. All grafts were custom-made grafts from the COOK Medical Fenestrated arch platform. Ninety-four (71.8%) had a scallop-and-single-fenestration design, 33 (25.2%) had a single fenestration and 4 (4.3%) a single scallop. For analysis purposes, these latter 4 grafts were excluded. Two main graft plans (Plans 1 and 2) were proposed after analysis with similar configuration (1 scallop with 30 mm width, 20 mm height, 12:00 position; 1 preloaded fenestration with 8 mm diameter, 26 mm from the top of the graft and 12:00 position; tapered, with a 193 mm length and 32 mm distal diameter) but with 2 different proximal diameters of 38 mm (Plan 1) and 44 mm (Plan 2), reaching an overall feasibility of 85.8% (n=109), being 47.2% (n=60) and 38.6% (n=49) for each design, respectively. CONCLUSION: The degree of overlap between the studied fenestrated and/or scalloped thoracic endovascular aneurysm repair (TEVAR) graft designs was high. Future studies analyzing these designs in a real-world cohort of patients are needed to further address off-the-shelf feasibility. CLINICAL IMPACT: In a multicenter study analyzing 127 fenestrated aortic arch endograft plans from 9 aortic centers, we found that the degree of overlap between the studied fenestrated and/or scalloped arch graft designs was high and that 2 proposed graft designs would be theoretically applicable in 85.8% of cases. Future studies analyzing these designs in a real-world cohort of patients are needed to further address off-the-shelf feasibility.

IL-11 is a crucial determinant of cardiovascular fibrosis.

Fibrosis is a common pathology in cardiovascular disease. In the heart, fibrosis causes mechanical and electrical dysfunction and in the kidney, it predicts the onset of renal failure. Transforming growth factor ß1 (TGFß1) is the principal pro-fibrotic factor, but its inhibition is associated with side effects due to its pleiotropic roles. We hypothesized that downstream effectors of TGFß1 in fibroblasts could be attractive therapeutic targets and lack upstream toxicity. Here we show, using integrated imaging-genomics analyses of primary human fibroblasts, that upregulation of interleukin-11 (IL-11) is the dominant transcriptional response to TGFß1 exposure and required for its pro-fibrotic effect. IL-11 and its receptor (IL11RA) are expressed specifically in fibroblasts, in which they drive non-canonical, ERK-dependent autocrine signalling that is required for fibrogenic protein synthesis. In mice, fibroblast-specific Il11 transgene expression or Il-11 injection causes heart and kidney fibrosis and organ failure, whereas genetic deletion of Il11ra1 protects against disease. Therefore, inhibition of IL-11 prevents fibroblast activation across organs and species in response to a range of important pro-fibrotic stimuli. These results reveal a central role of IL-11 in fibrosis and we propose that inhibition of IL-11 is a potential therapeutic strategy to treat fibrotic diseases.

Homemade Candy Plug Using a Zenith Alpha Thoracic Stent-Graft for False Lumen Distal Occlusion in Acute-on-Chronic Type B Aortic Dissection.

Purpose: To report a candy-plug technique using a Zenith Alpha stent-graft to occlude the distal false lumen in a patient with a complicated chronic type B aortic dissection. Case Report: A 50-year-old male smoker presented with chest pain due to rapidly growing complicated chronic type B aortic dissection. Computed tomography angiography (CTA) showed the dissection extending from distal to the origin of the left subclavian artery (LSA) down to the left femoral artery. There was fusiform aneurysmal dilatation of the proximal descending aorta measuring up to 5.8 cm in diameter. He underwent left carotid-subclavian artery bypass, thoracic endovascular aortic repair with a Zenith Alpha stent-graft, a left common carotid artery chimney, and embolization of the proximal LSA. Serial CTA showed persistent false lumen flow. A decision was made to occlude the distal large false lumen using the candy-plug technique. A 44×125-mm Zenith Alpha stent-graft was used to prepare the candy plug. A gutter leak and a type Ia endoleak were embolized via a left brachial artery approach. At 2.5 years, imaging showed the candy plug in position, no endoleak, and the thrombosed false lumen in the thoracic aorta reduced in size. Conclusion: The candy-plug technique is useful in facilitating complete occlusion of the false lumen in chronic aortic dissection, which avoids an open procedure and the risk of higher morbidity.

Therapeutic Hypothermia May Improve Neurological Outcomes in Extracorporeal Life Support for Adult Cardiac Arrest.

BACKGROUND: Limited data exists on patients receiving therapeutic hypothermia during extracorporeal life support (ECLS). We investigated outcomes and prognostic factors in these patients. METHODS: A retrospective review was conducted for 225 consecutive adult patients treated with ECLS between July 2003 and January 2016. Extracorporeal life support was initiated for refractory cardiac arrest (>10 mins) in 79 patients (35.1%). Patient demographics, ECLS-related complications, in-hospital mortality and neurological outcomes were analysed. RESULTS: The mean age was 49.9±12.4 years. Sixty-two patients (78.5%) were male. The mean duration of CPR and ECLS were respectively, 32.0±23.3 mins and 5.4±4.0 days. Therapeutic hypothermia (34oC) was maintained for 24hours in 14 patients (17.7%). Thirty-five patients (44.3%) were weaned off ECLS. Twenty-one patients (26.6%) survived to hospital discharge with 16 (20.3%) recovering good neurological function. Compared to ECLS at normothermia, neurologically favourable survival was higher in the hypothermia group (42.9% vs 15.4%, p=0.020). Multivariable analysis identified a non-shockable rhythm [odds ratio (OR) 5.1, confidence interval (CI) 1.5-16.8], ischaemic hepatitis (OR 6.2, CI 1.1-33.6) and hypoxic ischaemic encephalopathy (OR 5.1, CI 1.5-17.1) as predictors of in-hospital mortality. Therapeutic hypothermia (OR 4.9, CI 1.2-20.4) and acute renal failure (OR 0.19, CI 0.05-0.70) were predictors of neurologically favourable survival. CONCLUSIONS: In this report of patients treated with ECLS, in-hospital survival and survival with good neurological performance were 26.6% and 20.3% respectively. A non-shockable rhythm, ischaemic hepatitis and hypoxic ischaemic encephalopathy were predictors of in-hospital mortality. Therapeutic hypothermia during ECLS was associated with improved neurological outcomes.

Safety and efficacy of cerebral embolic protection in transcatheter aortic valve implantation: an updated meta-analysis.

Background: The use of cerebral embolic protection devices during transcatheter aortic valve implantation (TAVI) reveals conflicting data. Aims: This updated meta-analysis aims to evaluate the efficacy and safety of the SENTINEL Cerebral Protection System. Methods: A literature search for relevant studies up to September 2022 was performed. Study outcomes were divided based on time period - overall (up to 30 days) and short (≤7 days). The outcomes studied include stroke (disabling, non-disabling), mortality, neuroimaging findings, transient ischaemic attack, acute kidney injury and major vascular and bleeding complications. Results: A total of 15 studies involving 294,134 patients were included. Regarding overall outcomes, significant reductions were noted for mortality (odds ratio [OR] 0.60, 95% confidence interval [CI]: 0.41-0.88; p=0.008), all stroke (OR 0.64, 95% CI: 0.46-0.88; p=0.006) and disabling stroke (OR 0.42, 95% CI: 0.23-0.74; p=0.003) using the SENTINEL device. No significant differences were noted for other outcomes. There was significant heterogeneity across the studies for mortality (p=0.013) and all stroke (p=0.003). Including only randomised data (n=4), there was only significant reduction in the incidence of disabling stroke (OR 0.39, 95% CI: 0.17-0.89; p=0.026) in the SENTINEL group. In studies reporting ≤7-day outcomes (n=8), use of the SENTINEL device demonstrated significantly lower rates of all stroke (p<0.001), disabling stroke (p<0.001) and major bleeding complications (p=0.02). No differences in neuroimaging outcomes were noted. Conclusions: In this updated meta-analysis, use of the SENTINEL Cerebral Protection System was associated with lower rates of mortality, all stroke and disabling stroke, although significant heterogeneity was noted for mortality and all stroke. Including exclusively randomised data, there was only significant reduction in the incidence of disabling stroke. No significant adverse outcomes with device use were noted.

Integrated regulation of tubulin tyrosination and microtubule stability by human α-tubulin isotypes.

Tubulin isotypes are critical for the functions of cellular microtubules, which exhibit different stability and harbor various post-translational modifications. However, how tubulin isotypes determine the activities of regulators for microtubule stability and modifications remains unknown. Here, we show that human α4A-tubulin, a conserved genetically detyrosinated α-tubulin isotype, is a poor substrate for enzymatic tyrosination. To examine the stability of microtubules reconstituted with defined tubulin compositions, we develop a strategy to site-specifically label recombinant human tubulin for single-molecule TIRF microscopy-based in vitro assays. The incorporation of α4A-tubulin into the microtubule lattice stabilizes the polymers from passive and MCAK-stimulated depolymerization. Further characterization reveals that the compositions of α-tubulin isotypes and tyrosination/detyrosination states allow graded control for the microtubule binding and the depolymerization activities of MCAK. Together, our results uncover the tubulin isotype-dependent enzyme activity for an integrated regulation of α-tubulin tyrosination/detyrosination states and microtubule stability, two well-correlated features of cellular microtubules.

Longitudinal analysis of thoracic aortic expansion in non-syndromic real-world patients.

Remodeling of the thoracic aorta is commonly seen and viewed as a precursor to an aortic aneurysm. However, while aneurysms have been shown to expand at a rate of approximately 1 mm annually, the expansion of the pre-aneurysmal aorta is poorly characterized, especially in relation to age, gender, and aortic size per se. We identified patients that had undergone echocardiography at least twice at a large university medical center. Diagnosis codes, medications, and blood test results were obtained from hospital records. Syndromic patients were excluded (e.g., Marfan's syndrome, bicuspid aortic valve). Final population comprised n = 24,928 patients (median age 61.2 years (inter-quartile range (IQR): 50.6-71.5); 55.8% males) that had undergone a median of 3 echocardiograms (2-4; range 2-27) during a median of 4.0 years (IQR: 2.3-6.2). Hypertension was present in 39.6% of patients and diabetes in 20.7%, median LV ejection fraction was 56.0% (IQR: 41.0-62.0). Aortic size measurements were analyzed in mixed models while clustering on individual patients. Mean expansion was determined for sinus of Valsalva as 1.93 (95% confidence interval; CI95: 1.87-1.99) mm per decade, and for ascending aorta as 1.76 (CI95: 1.70-1.82) mm per decade. Faster expansion was found in males, with larger aortic size, and younger age (p for interaction <0.05 for all). In conclusion, expansion of the thoracic aorta, in real world, non-syndromic patients, is slow and averages <2 mm per decade. This will help to inform management of this large patient group.

Network Meta-Analysis Comparing Transcatheter, Minimally Invasive, and Conventional Surgical Aortic Valve Replacement.

The landscape of aortic valve replacement (AVR) has evolved dramatically over the years, but time-varying outcomes have yet to be comprehensively explored. This study aimed to compare the all-cause mortality among 3 AVR techniques: transcatheter (TAVI), minimally invasive (MIAVR), and conventional AVR (CAVR). An electronic literature search was performed for randomized controlled trials (RCTs) comparing TAVI with CAVR and RCTs or propensity score-matched (PSM) studies comparing MIAVR with CAVR or MIAVR to TAVI. Individual patient data for all-cause mortality were derived from graphical reconstruction of Kaplan-Meier curves. Pairwise comparisons and network meta-analysis were conducted. Sensitivity analyses were performed in the TAVI arm for high risk and low/intermediate risk, as well as patients who underwent transfemoral (TF) TAVI. A total of 27 studies with 16,554 patients were included. In the pairwise comparisons, TAVI showed superior mortality to CAVR until 37.5 months, beyond which there was no significant difference. When restricted to TF TAVI versus CAVR, a consistent mortality benefit favoring TF TAVI was seen (shared frailty hazard ratio [HR] = 0.86, 95% confidence interval [CI] = 0.76 to 0.98, p = 0.024). In the network meta-analysis involving majority PSM data, MIAVR demonstrated significantly lower mortality than TAVI (HR = 0.70, 95% CI = 0.59 to 0.82) and CAVR (HR = 0.69, 95% CI = 0.59 to 0.80); this association remained compared with TF TAVI but with a lower extent of benefit (HR = 0.80, 95% CI = 0.65 to 0.99). In conclusion, the initial short- to medium-term mortality benefit for TAVI over CAVR was attenuated over the longer term. In the subset of patients who underwent TF TAVI, a consistent benefit was found. Among majority PSM data, MIAVR showed improved mortality compared with TAVI and CAVR but less than the TF TAVI subset, which requires validation by robust RCTs.

Impact of aortic annular size and valve type on haemodynamics and clinical outcomes after transcatheter aortic valve implantation.

INTRODUCTION: Data on patients with small aortic annuli (SAA) undergoing transcatheter aortic valve implantation (TAVI) are limited. We aim to describe the impact of aortic annular size, particularly SAA and TAVI valve type on valve haemodynamics, durability and clinical outcomes. METHOD: All patients in National Heart Centre Singapore who underwent transfemoral TAVI for severe symptomatic native aortic stenosis from July 2012 to December 2019 were included. Outcome measures include valve haemodynamics, prosthesis-patient mismatch (PPM), structural valve degeneration (SVD) and mortality. RESULTS: A total of 244 patients were included. The mean Society of Thoracic Surgeons score was 6.22±6.08, with 52.5% patients with small aortic annulus (<23mm), 33.2% patients with medium aortic annulus (23-26mm) and 14.3% patients with large aortic annulus (>26mm). There were more patients with self-expanding valve (SEV) (65.2%) versus balloon-expandable valve (BEV) (34.8%). There were no significant differences in indexed aortic valve area (iAVA), mean pressure gradient (MPG), PPM, SVD or mortality across all aortic annular sizes. However, specific to the SAA group, patients with SEV had larger iAVA (SEV 1.19±0.35cm2/m2 vs BEV 0.88±0.15cm2/m2, P<0.01) and lower MPG (SEV 9.25±4.88 mmHg vs BEV 14.17±4.75 mmHg, P<0.01) at 1 year, without differences in PPM or mortality. Aortic annular size, TAVI valve type and PPM did not predict overall mortality up to 7 years. There was no significant difference in SVD between aortic annular sizes up to 5 years. CONCLUSION: Valve haemodynamics and durability were similar across the different aortic annular sizes. In the SAA group, SEV had better haemodynamics than BEV at 1 year, but no differences in PPM or mortality. There were no significant differences in mortality between aortic annular sizes, TAVI valve types or PPM.

Does concurrent use of intra-aortic balloon pumps improve survival in patients with cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Does concurrent use of intra-aortic balloon pump (IABP) improve survival in patients with cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO)?'. Altogether 472 papers were found using the reported search, of which 3 level 2 systematic reviews represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The reported comparative outcomes were mortality, weaning off extracorporeal membrane oxygenation (ECMO), vascular complications and non-vascular complications. One systematic review demonstrated significantly lower in-hospital mortality with concurrent use of IABP and VA-ECMO, while the other 2 studies showed no difference in mortality. One paper reported on the weaning success from ECMO and demonstrated significantly higher weaning success with concurrent IABP usage. Another paper reported on the complications and showed no differences in vascular and non-vascular complications. We conclude that there was no significant improvement in survival with the concurrent use of IABP and VA-ECMO for a cardiogenic shock as compared to the use of VA-ECMO alone. However, the concurrent use of IABP with VA-ECMO improved weaning success from VA-ECMO. The incidence of vascular and non-vascular complications was similar with or without IABP usage.

Five-Meter Walk Test as a Predictor of Prolonged Index Hospitalization After Transcatheter Aortic Valve Implantation.

There are no studies evaluating comprehensive predictors of transcatheter aortic valve implantation (TAVI) outcomes encompassing frailty assessments in a South-East Asian cohort. In this longitudinal single-center cohort, all patients who underwent TAVI in a tertiary cardiac center and comprehensively assessed for frailty at baseline were included in a registry. The primary outcome was to investigate frailty indices predictive of prolonged index hospitalization after TAVI. Seventy-six patients with a mean age of 77.6 ± 8.5 years were included. Mean Society of Thoracic Society Predicted Risk of Mortality score was 5.2 ± 3.0, with 11 (14.5%) patients classified as high-risk (Society of Thoracic Society Predicted Risk of Mortality >8). Mean and median index hospitalization duration were 9.2 ± 5.6 and 7 [4.5 to 9.5] days, respectively. Univariate analysis demonstrated that lower hemoglobin (Hb) (p <0.01), longer 5-meter walk test (5MWT) (p <0.01), lower dominant hand grip strength (p <0.01), the use of transaortic access (p = 0.01), new atrial fibrillation post-TAVI (p <0.01), and lower postprocedural Hb (p <0.01) were associated with longer index hospitalization duration. Multivariate linear regression demonstrated preoperative Hb, preoperative atrial fibrillation and 5MWT were independent baseline predictors of index hospitalization duration (p <0.05). Additionally, a 5MWT cutoff of 11 seconds (0.45 m/s) had a high specificity (88.6%) in predicting prolonged index hospitalization duration. In conclusion, this is the first comprehensive frailty assessment in a South-East Asian cohort demonstrating 5MWT to be a significant predictor of prolonged index hospitalization. This simple and effective frailty assessment index may be considered to optimize patient selection for TAVI.

Long-term prognosis in patients with end-stage renal disease after coronary artery bypass grafting.

BACKGROUND: Cardiovascular disease is a major cause of morbidity and mortality in patients with end-stage renal disease (ESRD). Coronary artery bypass grafting (CABG) is beneficial in selected patients with ESRD. This study investigates the survival outcomes and prognostic factors in ESRD patients who underwent CABG. METHODS: A retrospective analysis was performed for 149 patients with ESRD who underwent isolated CABG between 2006 and 2015. RESULTS: Mean age was 59.4±8.7 years and 106 patients (71.1%) were male. Operative mortality occurred in 20 patients (13.4%). Overall survival was 81.1%±3.2% at 1 year, 41.5%±4.3% at 5 years and 19.2%±4.2% at 10 years. Median survival was 4.3 years. Multivariable analysis identified age [P=0.001, odds ratio (OR): 1.15 per 1-year increase, 95% confidence interval (CI): 1.06-1.25], preoperative left ventricular ejection fraction (LVEF) (P=0.020, OR: 0.94, 95% CI: 0.89-0.99) and non-elective status of operation (P=0.049, OR: 3.34, 95% CI: 1.00-11.1) as predictors of operative mortality. Cox regression analysis identified age [P<0.001, hazard ratio (HR): 1.05 per 1-year increase, 95% CI: 1.03-1.08], New York Heart Association (NYHA) class III or IV status (P=0.010, HR: 1.75, 95% CI: 1.15-2.67) and the use of a left internal mammary artery (LIMA) to left anterior descending artery (LIMA-LAD) graft (P=0.029, HR: 0.42, 95% CI: 0.19-0.92) as factors influencing long-term survival. CONCLUSIONS: CABG is associated with high operative mortality and poor long-term survival in ESRD patients. Age and NYHA class influenced late survival. LIMA-LAD grafting conferred a long-term survival advantage.

Impact of Chronic Kidney Disease on Outcomes in Transcatheter Aortic Valve Implantation.

INTRODUCTION: Chronic kidney disease (CKD) is a significant comorbidity in aortic stenosis (AS) patients. We examined the impact of baseline CKD, postoperative acute kidney injury (AKI) and CKD progression on clinical outcomes in patients who underwent transcatheter aortic valve implantation (TAVI). MATERIALS AND METHODS: Consecutive patients with severe AS who underwent TAVI were classified into CKD stages 1-2 (≥60 mL/min/1.72m2), 3 (30-59 mL/min/1.73m2) and 4-5 (<30 mL/min/1.73m2 or dialysis) based on estimated glomerular filtration rate (eGFR). Primary outcome was mortality and secondary outcomes included 1-year echocardiographic data on aortic valve area (AVA), mean pressure gradient (MPG) and aortic regurgitation (AR). RESULTS: A total of 216 patients were included. Higher eGFR was associated with lower overall mortality (adjusted hazards ratio [AHR] 0.981, 95% confidence interval [CI] 0.968-0.993, P = 0.002). CKD 4-5 were associated with significantly higher mortality from non-cardiovascular causes (P <0.05). Patients with CKD 3-5 had higher incidence of moderate AR than those with CKD 1-2 (P = 0.010); no difference in AVA and MPG was seen. AKI patients had higher mortality (P = 0.008), but the effect was attenuated on multivariate analysis (AHR 1.823, 95% CI 0.977-3.403, P = 0.059). Patients with CKD progression also had significantly higher mortality (AHR 2.969, 95% CI 1.373-6.420, P = 0.006). CONCLUSION: CKD in severe AS patients undergoing TAVI portends significantly higher mortality and morbidity. Renal disease progression impacts negatively on outcomes and identifies a challenging subgroup of patients for optimal management.

Type 2 Endoleaks: Common and Hard to Eradicate yet Benign?

PURPOSE: The exact significance of type 2 endoleaks (T2ELs) and the indication and efficacy of treatment are widely debated. We report our experience with managing T2ELs in a tertiary Asian centre. MATERIALS AND METHODS: This was a retrospective study of patients who underwent endovascular abdominal aortic aneurysm repair (EVAR) between February 2006 and December 2016. Patients with T2ELs were identified, and their data were analysed. RESULTS: A total of 156 patients underwent EVAR, of which 67 (42.9%) developed T2ELs. Seven were lost to follow-up. The remaining 60 patients had a mean follow-up period of 50.3 ± 33.9 months-34 (56.7%) experienced T2ELs early and the rest (43.3%) had late T2ELs. Forty-one patients had isolated T2EL, whilst 19 had concomitant T1EL and/or T3EL. Spontaneous resolution occurred in 25 patients (41.7%). All T2ELs with stable sac size were on continued surveillance. Amongst those with persistent T2ELs associated with sac growth (n = 17), 14 underwent intervention, of which 7 (50%) received > 1 embolisation procedure. A total of 16 transarterial embolisation and 8 translumbar embolisation procedures were performed. Technical success rate was 75%. In the intervention group, 5 (35.7%) had complete and sustained resolution, 7 had persistent/recurrent T2ELs but stable sac size, and 2 had progressive sac expansion. Overall mortality due to sac rupture occurred in 2 patients with concomitant T2EL and T1EL/T3EL. CONCLUSION: T2ELs are common, albeit mostly benign if occurring in isolation and not in association with sac growth. Achieving complete T2EL resolution with embolisation is difficult even with reinterventions. LEVEL OF EVIDENCE: Level 2B, retrospective study.

Prognostic Factors for Survival After Extracorporeal Membrane Oxygenation for Cardiogenic Shock.

The aim of this study is to examine factors that can predict mortality in patients that have veno-arterial extracorporeal membrane oxygenation (VA-ECMO) instituted for cardiogenic shock. A single-center, retrospective study of 127 patients who underwent VA-ECMO for cardiogenic shock between January 2003 and December 2017 was conducted. Eighty-three (65%) patients survived to weaning or bridging therapy. Complications on VA-ECMO include: hemorrhage (40%), stroke (14%), requirement for dialysis (42%), and limb ischemia (24%). Univariate analysis revealed shorter ECMO duration, higher body mass index, preimplantation creatinine > 100 mmol/l, lower preimplantation serum albumin, and the development of stroke or limb ischemia on ECMO to be significantly associated with mortality while on ECMO. Multivariate analysis by logistic regression found shorter ECMO duration and lower preimplantation serum albumin to be significantly associated with mortality. VA-ECMO is an effective strategy in treating patients with cardiogenic shock and provides a reasonable chance of survival to weaning or bridging to other therapy. Preimplantation hypoalbuminemia, preimplantation serum creatinine > 100 mmol/l, and the development of stroke and limb ischemia while on VA-ECMO are strongly associated with mortality.

Clinical Updates on the Diagnosis and Management of Chronic Thromboembolic Pulmonary Hypertension.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is a known sequela after acute pulmonary embolism (PE). It is a debilitating disease, and potentially fatal if left untreated. This review provides a clinically relevant overview of the disease and discusses the usefulness and limitations of the various investigational and treatment options. METHODS: A PubMed search on articles relevant to PE, pulmonary hypertension, CTEPH, pulmonary endarterectomy, and balloon pulmonary angioplasty were performed. A total of 68 articles were found to be relevant and were reviewed. RESULTS: CTEPH occurs as a result of non-resolution of thrombotic material, with subsequent fibrosis and scarring of the pulmonary arteries. Risk factors have been identified, but the underlying mechanisms have yet to be fully elucidated. The cardinal symptom of CTEPH is dyspnoea on exertion, but the diagnosis is often challenging due to lack of awareness. The ventilation/perfusion scan is recommended for screening for CTEPH, with other modalities (eg. dual energy computed tomography pulmonary angiography) also being utilised in expert centres. Conventional pulmonary angiography with right heart catheterisation is important in the final diagnosis of CTEPH. CONCLUSION: Operability assessment by a multidisciplinary team is crucial for the management of CTEPH, as pulmonary endarterectomy (PEA) remains the guideline recommended treatment and has the best chance of cure. For inoperable patients or those with residual disease post-PEA, medical therapy or balloon pulmonary angioplasty are potential treatment options.

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.

Restrictive mitral valve annuloplasty for chronic ischaemic mitral regurgitation: outcomes of flexible versus semi-rigid rings.

BACKGROUND: Restrictive mitral annuloplasty is the mainstay of surgical correction of chronic ischaemic mitral regurgitation (CIMR). Long-term data on the various types of annuloplasty rings is limited. The aim of this study was to investigate the clinical and echocardiographic outcomes of restrictive mitral annuloplasty in patients with CIMR, comparing the use of flexible versus semi-rigid annuloplasty rings. METHODS: A retrospective review was conducted for 133 patients with CIMR who underwent restrictive mitral annuloplasty at our institution between 1999 and 2015. Patient demographics and postoperative outcomes were analyzed. RESULTS: Mean age was 61.9±9.2 years and 103 patients (77.4%) were male. All patients underwent coronary artery bypass grafting, with a mean of 3.3±0.8 grafts. Flexible rings was implanted in 39 patients (29.3%, group F) and semi-rigid rings in 94 (70.7%, group R). Preoperative New York Heart Association class was III/IV in 104 patients (78.2%). Mean preoperative left ventricular ejection fraction was 28.8%±10.2%. Preoperative mitral regurgitation was moderate in 51 patients (38.3%) and severe in 82 (61.7%). In-hospital mortality occurred in 11 patients (8.3%). Overall survival at 1, 5 and 10 years were, respectively, 86.4%, 69.7% and 45.9%. At 10 years, overall survival (group F 53.1%, group R 40.0%, P=0.330) and freedom from moderate to severe MR (group F 53.1%, group R 53.8%, P=0.725) did not differ significantly. Freedom from hospitalization for heart failure was 59.3%. Left ventricular reverse remodelling, defined as a reduction of left ventricular end-systolic volume index >15%, occurred more commonly in Group R (51.1%) compared to Group F (23.1%), P=0.003. CONCLUSIONS: Restrictive mitral annuloplasty was associated with an operative mortality of 8.3%. Heart failure symptoms and significant MR recur in approximately 40% of patients after 10 years. Survival remained suboptimal and was not influenced by the type of annuloplasty ring.

Staphylococcal driveline infections are the predominant type of left ventricular assist device associated infections in Singapore.

BACKGROUND: Left ventricular assist device (LVAD) associated infections (LVADIs) have substantial morbidity and mortality. We aim to describe the incidence and epidemiology of LVADIs in an Asian cohort. This is currently not well studied. METHODS: We conducted a retrospective review of 52 patients who underwent LVAD implantation from 1 May 2009-31 December 2014 in National Heart Centre Singapore. LVADIs were defined based on definitions proposed by the International Society for Heart and Lung Transplantation. RESULTS: There were 39 males and 13 females. Seventy-three percent had Heartmate II LVAD implant while 27% received Heartware HVAD. Eighty-one percent were implanted as bridge to heart transplantation, 19% as destination therapy. Forty-five episodes of LVADIs occurred in 25 patients. Overall LVADI incidence was 47.5 cases per 100 patient-years. Driveline infections (58%) were the commonest type of LVADI. The commonest causative organisms were coagulase-negative staphylococci (33%), Staphylococcus aureus (31%) and Corynebacterium species (19%). Twelve percent of patients with LVADI required surgical debridement and one patient required pump exchange due to pump pocket infection. All-cause mortality was 13%. CONCLUSIONS: The findings of our study add to the understanding and epidemiology of LVADIs, particularly in the Asian setting. This can contribute to the development of evidence based strategies to prevent and manage LVADIs.

Left Circumflex Artery Rupture with Left Atrial Tamponade and Functional Mitral Stenosis.

The growth in percutaneous transluminal devices has enabled operators to tackle more complex, native, and post-bypass surgery anatomy. However, complications such as coronary artery dissection, coronary perforation, retrograde aortic dissection, arrhythmias, and acute coronary syndrome still occur with resulting mortality rates of up to 4.2% in complex interventions. Perforation of the circumflex artery is of particular interest in view of its position and relation to the surrounding cardiac structures. This is a site of potential fluid collection, and as the left atrium is fixed to the parietal pericardium at the entry of the pulmonary veins, fluid in the oblique sinus can accumulate enough pressure to compress the left atrium and the coronary sinus. We present a case of left circumflex artery perforation which demonstrates the physiologic complications of coronary sinus and left atrial compression and the resultant functional mitral stenosis.