The Clinical SYNTAX score predicts survival better than the SYNTAX score in coronary revascularization

BACKGROUND

The Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) trial showed that the SYNTAX score (SS) is a useful tool for customizing revascularization treatment for patients with multivessel coronary disease. In the past decade, the Clinical SS (CSS) has emerged as a comprehensive tool. This novel tool considers the SS as well as patient clinical parameters such as age, creatinine clearance, and ejection fraction, which were shown to be relevant for patient prognosis. Thus, in the current work we set out to compare the survival predictive values of the SS versus the CSS and their future application in real-world implementation of the revascularization guidelines.

METHODS

This study was a subanalysis of data collected in a prospective national registry in Israel that enrolled consecutive patients with left main and/or 2- to 3-vessel coronary artery disease involving the proximal or mid-left anterior descending artery; the MULTI-vessel Coronary Artery Disease (MULTICAD). The revascularization method was chosen by the physicians taking care of the patients at each hospital and the patients were followed for 5 years. Patients were categorized according to their SS, the CSS, and their revascularization method (primary coronary intervention [PCI] vs coronary artery bypass grafting [CABG]) and patient survival were compared.

RESULTS

A total of 585 patients were enrolled in the study and were followed for 5 years. The median CSS was 27, with 288 patients showing a CSS ≥27, with a mean CSS of 47.85 and a mean SS of 29.05. At 3 and 5 years post-treatment, the CSS ≥27 group had a lower survival probability, CSS ≥27 was associated with a lower survival probability among patients who underwent PCI compared with those who underwent CABG. More specifically, the high-CSS CABG group had a 5-year mortality rate of 16.8%, whereas the high-CSS PCI group had a 5-year mortality rate of 32.2%. In a comparison of SS with CSS for the 5-year mortality outcome prediction, CSS was superior to SS with a higher area under the curve.

CONCLUSIONS

This prospective registry of real-world revascularization strategies in patients with multivessel disease showed that CSS is a better predictive tool of postrevascularization survival than SS. Moreover, it showed that surgical revascularization in patients with CSS ≥27 is associated with better all-cause mortality outcome after CABG as compared with after PCI. This attests to the need for a score that considers clinical parameters in a real-world scenario.

Ubiquitin Proteasome System Role in Diabetes-Induced Cardiomyopathy

This study investigated modifications to the ubiquitin proteasome system (UPS) in a mouse model of type 2 diabetes mellitus (T2DM) and their relationship to heart complications. db/db mice heart tissues were compared with WT mice tissues using RNA sequencing, qRT-PCR, and protein analysis to identify cardiac UPS modifications associated with diabetes. The findings unveiled a distinctive gene profile in the hearts of db/db mice with decreased levels of nppb mRNA and increased levels of Myh7, indicating potential cardiac dysfunction. The mRNA levels of USP18 (deubiquitinating enzyme), PSMB8, and PSMB9 (proteasome β-subunits) were down-regulated in db/db mice, while the mRNA levels of RNF167 (E3 ligase) were increased. Corresponding LMP2 and LMP7 proteins were down-regulated in db/db mice, and RNF167 was elevated in Adult diabetic mice. The reduced expression of LMP2 and LMP7, along with increased RNF167 expression, may contribute to the future cardiac deterioration commonly observed in diabetes. This study enhances our understanding of UPS imbalances in the hearts of diabetic mice and raises questions about the interplay between the UPS and other cellular processes, such as autophagy. Further exploration in this area could provide valuable insights into the mechanisms underlying diabetic heart complications and potential therapeutic targets.

Improved immunogenicity following the third dose of BNT162b2 mRNA vaccine in heart transplant recipients

OBJECTIVES

The immunogenicity of two-dose severe acute respiratory syndrome coronavirus 2 vaccine is lower among heart transplant (HTx) recipients, compared with the general population. Our aim was to assess the immunogenicity of a third-dose vaccine in HTx recipients.

METHODS

This is a prospective cohort study of HTx recipients who received a third dose of the BNT162b2 vaccine. Immunogenicity was assessed by serum levels of anti-spike immunoglobulin G (S-IgG), taken at baseline and 14-28 days after the third dose. Titres above 50 U/ml were interpreted positive.

RESULTS

We Included 42 HTx recipients at a median age of 65 years [interquartile range (IQR) 58-70]. At baseline, the median of 27 days (IQR 13-42) before the third dose and the median titre of the whole group was 18 U/ml (IQR 4-130). Only 14 patients (33%) were S-IgG seropositive. After the third dose, the proportion of seropositive patients increased significantly to 57% (P = 0.05) and the median titre increased significantly to 633 U/ml (IQR 7-6104, P < 0.0001). Younger age at HTx (OR per 1-year decrease 1.07, P = 0.05), low tacrolimus serum level (OR per 1-unit decrease 2.28, P = 0.02), mammalian target of rapamycin use (OR 13.3, P = 0.003), lack of oral steroids use (OR 4.17, P = 0.04) and lack of calcineurin inhibitor use (71% of responders vs 100% non-responders received calcineurin inhibitors, P = 0.01) were predictors of seropositive result after the third dose. However, no significant association was detected following adjustment for baseline S-IgG titre.

CONCLUSIONS

Third-dose booster of BNT162b2 vaccine significantly increased immunogenicity among HTx recipients who previously received a two-dose vaccine.

Combined mechanical circulatory support for ventricular fibrillation in left ventricular assist device patient

Ventricular fibrillation, a life-threatening ventricular arrhythmia, may result in pulselessness, loss of consciousness and sudden cardiac death. In this case report, we describe our experience in managing a 54-year-old man with HeartMate3 left ventricular assist device (LVAD) as a bridge to transplantation due to dilated non-ischemic cardiomyopathy, presenting with incessant ventricular arrhythmia for 35 days despite multiple attempts to restore normal rhythm with external direct current cardioversion and anti-arrhythmic medications. The patient remained stable in ventricular arrhythmia with no progression to asystole, but hemodynamic collapse due to right heart failure occurred in the third week. Combined use of two mechanical circulatory support devices (LVAD with VA ECMO) was needed to achieve haemodynamic and metabolic stability, eventually leading to successful heart transplantation in the index admission. The patient was discharged home 2 weeks after transplantation in good clinical condition.

Six-months immunogenicity of BNT162b2 mRNA vaccine in heart transplanted and ventricle assist device-supported patients

AIMS

To assess the 6 months immunogenicity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine in a population of heart transplanted (HTx) recipients and left ventricular assist device (LVAD)-supported patients.

METHODS AND RESULTS

A prospective single-centre cohort study of HTx recipients and LVAD-supported patients who received a two-dose SARSCoV-2 mRNA vaccine (BNT162b2, Pfizer-BioNTech). Whole blood for anti-spike IgG (S-IgG) antibodies were drawn at 6 months after the first vaccine dose. S-IgG data at 6 weeks were available for a subgroup of HTx recipients. S-IgG ≥ 50 AU/mL were interpreted positive. The cohort included 53 HTx recipients and 18 LVAD-supported patients. The median time from HTx or LVAD implantation to the 1st vaccine dose was 90 (IQR 30, 172) months and 22 (IQR 6, 78) months, respectively. The seropositivity rates of S-IgG antibodies and their titre levels in HTx recipients and LVAD-supported patients were 45% and 83% respectively, (P = 0.006), and 35 (IQR 7, 306) AU/mL and 311 (IQR 86, 774) AU/mL, respectively, (P = 0.006). Reduced SARSCoV-2 vaccine immunogenicity in HTx recipients was associated with older age [odds ratio (OR) 0.917 confidence interval (CI 0.871, 0.966), P = 0.011] and with the use of anti-metabolites-based immunosuppressive regimens [OR 0.224 (CI 0.065, 0.777), P = 0.018]. mTOR inhibitors were associated with higher immunogenicity [OR 3.1 (CI 1.01, 9.65), P = 0.048]. Out of 13 HTx recipients who were S-IgG seropositive at 6 weeks after the first vaccine dose, 85% remained S-IgG seropositive at 6 month follow-up.

CONCLUSIONS

At 6 months post-vaccination, S-IgG immunogenicity in HTx recipients is low, particularly in older HTx recipients and in those treated with anti-metabolites drugs.

Right and left ventricular assist devices are an option for bridge to heart transplant

Background

Patients with a left ventricular assist device with right ventricular failure are prioritized on the heart transplant waitlist; however, their post-transplant survival is less well characterized. We aimed to determine whether pretransplant right ventricular failure affects postoperative survival in patients with a left ventricular assist device as a bridge to transplant.

Methods

We performed a retrospective review of the 2005-2018 Organ Procurement and Transplantation Network/United Network for Organ Sharing registry for candidates aged 18 years or more waitlisted for first-time isolated heart transplantation after left ventricular assist device implantation. Candidates were stratified on the basis of having right ventricular failure, defined as the need for right ventricular assist device or intravenous inotropes. Baseline demographic and clinical characteristics were compared among the 3 groups, and post-transplant survival was assessed.

Results

Our cohort included 5605 candidates who met inclusion criteria, including 450 patients with right ventricular failure, 344 patients with a left ventricular assist device and intravenous inotropes as a bridge to transplant, 106 patients with a left ventricular assist device and right ventricular assist device, and 5155 patients with a left ventricular assist device as a bridge to transplant without the need for right side support. Compared with patients without right ventricular failure, patients with a left ventricular assist device as a bridge to transplant with right ventricular failure were younger (median age 51 years, 55 vs 56 years, P < .001) and waited less time for organs (median 51 days, 93.5 vs 125 days, P < .001). These patients also had longer post-transplant length of stay (median 18 days, 20 vs 16 days, P < .001). Right ventricular failure was not associated with decreased post-transplant long-term survival on unadjusted Kaplan–Meier analysis (P = .18). Neither preoperative right ventricular assist device nor intravenous inotropes independently predicted worse survival on multivariate Cox proportional hazards analysis. However, pretransplant liver dysfunction (total bilirubin >2) was an independent predictor of worse survival (hazard ratio, 1.74; 95% confidence interval, 1.39-2.17; P < .001), specifically in the left ventricular assist device group and not in the left ventricular assist device + right ventricular assist device/intravenous inotropes group.

Conclusions

Patients with biventricular failure are prioritized on the waiting list, because their critical pretransplant condition has limited impact on their post-transplant survival (short-term effect only); thus, surgeons should be confident to perform transplantation in these severely ill patients. Because liver dysfunction (a surrogate marker of right ventricular failure) was found to affect long-term survival in patients with a left ventricular assist device, surgeons should be encouraged to perform transplantation in these severely ill patients after a recipient's optimization by inotropes or a right ventricular assist device because even when the bilirubin level is elevated in these patients (treated with right ventricular assist device/inotropes), their long-term survival is not affected. Future studies should assess recipients' optimization before organ acceptance to improve long-term survival.

Immunogenicity of the BNT162b2 mRNA vaccine in heart transplant recipients - a prospective cohort study

AIMS

To assess the short-term immunogenicity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine in a population of heart transplant (HTx) recipients. A prospective single-centre cohort study of HTx recipients who received a two-dose SARS-CoV-2 mRNA vaccine (BNT162b2, Pfizer-BioNTech).

METHODS AND RESULTS

Whole blood for anti-spike IgG (S-IgG) antibodies was drawn at days 21-26 and at days 35-40 after the first vaccine dose. Geometric mean titres (GMT) ≥50 AU/mL were interpreted positive. Included were 42 HTx recipients at a median age of 61 [interquartile range (IQR) 44-69] years. Median time from HTx to the first vaccine dose was 9.1 (IQR 2.6-14) years. Only 15% of HTx recipients demonstrated the presence of positive S-IgG antibody titres in response to the first vaccine dose [GMT 90 (IQR 54-229) AU/mL]. Overall, 49% of HTx recipients induced S-IgG antibodies in response to either the first or the full two-dose vaccine schedule [GMT 426 (IQR 106-884) AU/mL]. Older age [68 (IQR 59-70) years vs. 46 (IQR 34-63) years, P = 0.034] and anti-metabolite-based immunosuppression protocols (89% vs. 44%, P = 0.011) were associated with low immunogenicity. Importantly, 36% of HTx recipients who were non-responders to the first vaccine dose became S-IgG seropositive in response to the second vaccine dose. Approximately a half of HTx recipients did not generate S-IgG antibodies following SARS-CoV-2 two-dose vaccine.

CONCLUSIONS

The generally achieved protection from SARS-CoV-2 mRNA vaccination should be regarded with caution in the population of HTx recipients. The possible benefit of additive vaccine should be further studied.

Expression of the SARS-CoV-2 receptorACE2 in human heart is associated with uncontrolled diabetes, obesity, and activation of the renin angiotensin system

Background

Diabetic and obese patients are at higher risk of severe disease and cardiac injury in corona virus 2 (SARS-CoV-2) infections. Cellular entry of SARS-CoV-2 is mainly via the angiotensin-converting enzyme 2 (ACE2) receptor, which is highly expressed in normal hearts. There is a disagreement regarding the effect of factors such as obesity and diabetes on ACE2 expression in the human heart and whether treatment with renin–angiotensin system inhibitors or anti-diabetic medications increases ACE2 expression and subsequently the susceptibility to infection. We designed this study to elucidate factors that control ACE2 expression in human serum, human heart biopsies, and mice.

Methods

Right atrial appendage biopsies were collected from 79 patients that underwent coronary artery bypass graft (CABG) surgery. We investigated the alteration in ACE2 mRNA and protein expression in heart tissue and serum. ACE2 expression was compared with clinical risk factors: diabetes, obesity and different anti-hypertensive or anti-diabetic therapies. WT or db/db mice were infused with Angiotensin II (ATII), treated with different anti-diabetic drugs (Metformin, GLP1A and SGLT2i) were also tested.

Results

ACE2 gene expression was increased in diabetic hearts compared to non-diabetic hearts and was positively correlated with glycosylated hemoglobin (HbA1c), body mass index (BMI), and activation of the renin angiotensin system (RAS), and negatively correlated with ejection fraction. ACE2 was not differentially expressed in patients who were on angiotensin converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARBs) prior to the operation. We found no correlation between plasma free ACE2 and cardiac tissue ACE2 expression. Transmembrane serine protease 2 (TMPRSS2), metalloprotease ADAM10 and ADAM17 that facilitate viral-ACE2 complex entry and degradation were increased in diabetic hearts. ACE2 expression in mice was increased with ATII infusion and attenuated following anti-diabetic drugs treatment.

Conclusion

Patients with uncontrolled diabetes or obesity with RAS activation have higher ACE2 expressions therefore are at higher risk for severe infection. Since ACEi or ARBs show no effect on ACE2 expression in the heart further support their safety.

Health-related quality of life in left ventricular assist device-supported patients

Aims

This study aimed to evaluate the different health‐related quality of life (HR‐QoL) aspects in patients with both short‐term and long‐term duration LVAD support at pre‐specified time intervals.

Methods and results

We performed a single‐centre HR‐QoL analysis of short‐term and long‐term LVAD‐supported patients using the short version of the Kansas City Cardiomyopathy Questionnaire (KCCQ‐12) and the Changes in Sexual Functioning Questionnaire along with a survey to evaluate patients' social and driving routines. Data were collected at baseline and at 6 or 12 month follow‐up. Included were 46 patients with a median time from LVAD implantation of 1.1 [inter‐quartile range (IQR) 0.5, 2.6] years. The median KCCQ‐12 summary score was 56 (IQR 29, 74) with most favourable scores in the symptom frequency domain [75 (IQR 50, 92)] and worse scores in the physical limitation [42 (IQR 25, 75)] and QoL [44 (IQR 25, 75)] domains. No significant changes were apparent during study follow‐up [KCCQ‐12 summary score 56 (IQR 35, 80)], and no significant correlation between the KCCQ‐12 summary score and ventricular assist device‐support duration was detected (r = −0.036, P = 0.812). Sexual dysfunction was noted across all domains with a cumulative score of 31 (IQR 22, 42). Seventy‐six per cent of patients resumed driving after LVAD implantation, and 43% of patients reported they socialize with family and friends more frequently since surgery.

Conclusions

Short‐term and long‐term LVAD‐supported patients had impaired HR‐QoL and sexual function at baseline and at follow‐up yet reported an improvement in social interactions and independency. A broader spectrum of patient's reported HR‐QoL measures should be integrated into the pre‐LVAD implantation assessment and preparation.

An 18-month comparison of clinical outcomes between continuous-flow left ventricular assist devices

OBJECTIVES

In this study, we aimed to determine the comparative outcomes of patients supported with continuous-flow left ventricular assist devices (LVADs): HeartMate 2 (HM2), HeartWare (HW) and HeartMate 3 (HM3) in a real-world setting.

METHODS

The study was an investigator-initiated comparative retrospective analysis of patients who underwent continuous-flow LVAD implantation at our institution between 2008 and 2017. The follow-up duration was 18 months after implantation.

RESULTS

The study included 105 continuous-flow LVAD-supported patients of whom 51% (n = 54), 24% (25) and 25% (26) underwent implantation of HM2, HW and HM3, respectively. During follow-up, patients who were supported with HM3 versus either HM2 or HW LVADs demonstrated a lower risk of stroke (0% vs 26%, P < 0.001 and 0% vs 40%, P < 0.001, respectively) and lower rates of thrombosis (0% vs 31%, P < 0.001 and 0% vs 12%, P < 0.001, respectively), findings that were consistent with their calculated haemocompatibility scores (cumulative score 5, 89 and 56 for HM3, HM2 and HW, respectively, P < 0.001). Moreover, patients supported with HM3 versus HW had fewer unplanned hospitalizations [median 1 (25th-75th interquartile range 0-2) vs 3 (interquartile range 2-4), P = 0.012]. Importantly, survival free from stroke or device exchange was higher in patients supported with HM3 compared with either the HM2 or the HW LVADs [hazard ratio (HR) 2.77, confidence interval (CI) 1.13-6.78; P = 0.026 and HR 2.70, CI 1.01-7.20; P = 0.047, respectively].

CONCLUSIONS

HM3 device currently presents better prognostic and adverse events profiles when compared with the HM2 or the HW LVADs. A larger-scale head-to-head comparison between the devices is warranted in order to confirm our findings.

Abdominal Surgery in Patients with a Ventricular Assist Device: A Single Center Experience in Israel

BACKGROUND

Left ventricular assist devices (LVADs) are used more commonly in patients with advanced-stage heart failure. Some of these patients may require elective or urgent abdominal surgical procedures.

OBJECTIVES

To determine the outcomes of the management of LVAD-supported patients who underwent elective and urgent abdominal surgical procedures in our institution.

METHODS

A retrospective review was conducted on 93 patients who underwent LVAD implantation between August 2008 and January 2017. All abdominal surgeries in these patients were studied, and their impact on postoperative morbidity and mortality Ten patients underwent abdominal surgical procedures. Of these procedures, five were emergent and five were elective. The elective cases included one bariatric surgery for morbid obesity, one hiatal hernia repair, two cholecystectomies, and one small bowel resection for a carcinoid tumor. The emergency cases included suspected ischemic colitis, right colectomy for bleeding adenocarcinoma, laparotomy due to intraabdominal bleeding, open cholecystectomy for gangrenous cholecystitis, and laparotomy for sternal and abdominal wall infection. All patients undergoing elective procedures survived. Of the five patients who underwent emergency surgery, three died (60%, P = 0.16) and one presented with major morbidity. One of the two survivors required reintervention. In total, 12 interventions were performed on this group of patientswas evaluated.

RESULTS

Ten patients underwent abdominal surgical procedures. Of these procedures, five were emergent and five were elective. The elective cases included one bariatric surgery for morbid obesity, one hiatal hernia repair, two cholecystectomies, and one small bowel resection for a carcinoid tumor. The emergency cases included suspected ischemic colitis, right colectomy for bleeding adenocarcinoma, laparotomy due to intraabdominal bleeding, open cholecystectomy for gangrenous cholecystitis, and laparotomy for sternal and abdominal wall infection. All patients undergoing elective procedures survived. Of the five patients who underwent emergency surgery, three died (60%, P = 0.16) and one presented with major morbidity. One of the two survivors required reintervention. In total, 12 interventions were performed on this group of patients.

CONCLUSIONS

It is safe to perform elective abdominal procedures for LVAD-supported patients. The prognosis of these patients undergoing emergency surgery is poor and has high mortality and morbidity rates.

Do Colchicine and Prednisone Affect the Rate of Recurrence of Post-Pericardiotomy Syndrome

BACKGROUND

Post-pericardiotomy syndrome (PPS) is a major cause of pericarditis, yet data on the risk of recurrence are limited, and the impact of steroids and colchicine in this context is unknown.

OBJECTIVES

To examine the effect of prednisone and colchicine on the rate of recurrence of PPS.

METHODS

Medical files of patients diagnosed with PPS were reviewed to extract demographic, echocardiographic, X-ray imaging, and follow-up data.

RESULTS

The study comprised 132 patients (57% men), aged 27-86 years. Medical treatment included prednisone in 80 patients, non-steroidal anti-inflammatory agents in 41 patients, colchicine monotherapy in 2 patients, and no anti-inflammatory therapy in 9 patients. Fifty-nine patients were given colchicine for prevention of recurrence. The patients were followed for 5-110 months (median 64 months). Recurrent episodes occurred in 15 patients (11.4%), 10 patients had a single episode, 4 patients had two episodes, and one patient had three episodes. The rate of recurrence was lower in patients receiving colchicine compared to patients who did not (8.5% vs. 13.7%), and in patients not receiving vs. receiving prednisone (7.7% vs. 13.8%) but the differences were non-significant. Twenty-three patients died and there were no recurrence-related deaths.

CONCLUSIONS

The rate of recurrence after PPS is low and multiple recurrences are rare. The survival of patients with recurrent PPS is excellent. Prednisone pre-treatment was associated with a numerically higher rate of recurrence and colchicine treatment with a numerically lower rate, but the differences were non-significant.

Sodium-glucose cotransporter 2 inhibitor Dapagliflozin attenuates diabetic cardiomyopathy

Background

Diabetes mellitus type 2 (DM2) is a risk factor for developing heart failure but there is no specific therapy for diabetic heart disease. Sodium glucose transporter 2 inhibitors (SGLT2I) are recently developed diabetic drugs that primarily work on the kidney. Clinical data describing the cardiovascular benefits of SGLT2Is highlight the potential therapeutic benefit of these drugs in the prevention of cardiovascular events and heart failure. However, the underlying mechanism of protection remains unclear. We investigated the effect of Dapagliflozin—SGLT2I, on diabetic cardiomyopathy in a mouse model of DM2.

Methods

Cardiomyopathy was induced in diabetic mice (db/db) by subcutaneous infusion of angiotensin II (ATII) for 30 days using an osmotic pump. Dapagliflozin (1.5 mg/kg/day) was administered concomitantly in drinking water. Male homozygous, 12–14 weeks old WT or db/db mice (n = 4–8/group), were used for the experiments. Isolated cardiomyocytes were exposed to glucose (17.5–33 mM) and treated with Dapagliflozin in vitro. Intracellular calcium transients were measured using a fluorescent indicator indo-1.

Results

Angiotensin II infusion induced cardiomyopathy in db/db mice, manifested by cardiac hypertrophy, myocardial fibrosis and inflammation (TNFα, TLR4). Dapagliflozin decreased blood glucose (874 ± 111 to 556 ± 57 mg/dl, p < 0.05). In addition it attenuated fibrosis and inflammation and increased the left ventricular fractional shortening in ATII treated db/db mice. In isolated cardiomyocytes Dapagliflozin decreased intracellular calcium transients, inflammation and ROS production. Finally, voltage-dependent L-type calcium channel (CACNA1C), the sodium–calcium exchanger (NCX) and the sodium–hydrogen exchanger 1 (NHE) membrane transporters expression was reduced following Dapagliflozin treatment.

Conclusion

Dapagliflozin was cardioprotective in ATII-stressed diabetic mice. It reduced oxygen radicals, as well the activity of membrane channels related to calcium transport. The cardioprotective effect manifested by decreased fibrosis, reduced inflammation and improved systolic function. The clinical implication of our results suggest a novel pharmacologic approach for the treatment of diabetic cardiomyopathy through modulation of ion homeostasis.

Long-term Outcomes of Contemporary Coronary Revascularization by Percutaneous Coronary Intervention or Coronary Artery Bypass Grafting in Young Adults

BACKGROUND

Current guidelines for choosing between revascularization modalities may not be appropriate for young patients.

OBJECTIVES

To compare outcomes and guide treatment options for patients < 40 years of age, who underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) between 2008 and 2018.

METHODS

Outcomes were compared for 183 consecutive patients aged < 40 years who underwent PCI or CABG between 2008 and 2018, Outcomes were compared as time to first event and as cumulative events for non-fatal outcomes.

RESULTS

Mean patient age was 36.3 years and 96% were male. Risk factors were similar for both groups. Drug eluting stents were implemented in 71% of PCI patients and total arterial revascularization in 74% of CABG patients. During a median follow-up of 6.5 years, 16 patients (8.6%) died. First cardiovascular events occurred in 35 (38.8%) of the PCI group vs. 29 (31.1%) of the CABG group (log rank P = 0.022), repeat events occurred in 96 vs. 51 (P < 0.01), respectively. After multivariate adjustment, CABG was associated with a significantly reduced risk for first adverse event (hazard ratio [HR] 0.305, P < 0.01) caused by a reduction in repeat revascularization. CABG was also associated with a reduction in overall repeat events (HR 0.293, P < 0.01). There was no difference in overall mortality between CABG and PCI.

CONCLUSIONS

Young patients with coronary disease treated by CABG showed a reduction in the risk for non-fatal cardiac events. Mortality was similar with CABG and PCI.

P5427Mid-term comparison of clinical outcomes between continuous-flow left ventricular assist devices

Background

Continuous-flow left ventricular assist devices (cf-LVADs) are increasingly applied in patients with advanced heart failure (HF). Comparative data regarding cf-LVADs are lacking. We aim to determine the outcomes of patients supported with HeartMate 2 (HM2), HeartWare (HW) and HeartMate 3 (HM3).

Methods

A retrospective analysis of patients who underwent cf-LVAD implantation at our institution between 2008–2017. Follow-up duration was 18 months post implantation.

Results

Included were 105 cf-LVAD-supported patients of whom 51% (n=54), 24% (25) and 25% (26) underwent implantation of HM2, HW and HM3, respectively. Patients supported with HM3 versus HM2 had lower risk of thrombosis (0% vs. 37%, p=0<0.001), while patients supported with HM3 versus HW had lower risk of non-GI bleeding (15% vs. 46%, HR 0.28, CI 0.095, 0.85, p=0.024) and reduced unplanned hospitalizations (median 1 (interquartile range 0, 3) vs. 3 (interquartile range 2, 11), p=0.001). Patients supported with HM3 had a reduced risk of stroke compared with either HM2 or HW (0% vs. 26%, p=0.033 and 0% vs. 42%, p=0.005, respectively). Importantly, survival free from stroke or device exchange was higher in patients with HM3 compared to patients supported with either HM2 or HW (100% vs. 72%, p=0.029 and 100% vs. 56%, p=0.003, respectively) (Figure).

Mid-term event-free survival by VAD type

Conclusions

HM3 device presents the best currently available prognostic and adverse events profile when compared to HM2 and HW. We believe that HM3 should be offered as the device of choice for mechanically-supported advanced HF patients

Trimodally treatment for stage IIIa NSCLC patients increases survival while not effecting surgical mortality or complexity

Introduction

Advanced non-small cell lung cancer (NSCLC) is still a therapeutic challenge as the 5-year survival is under 30%. The optimal treatment regimen is still under debate.

Hypothesis

Neo adjuvant (NA) treatment given pre-pneumonectomy does not increase surgical complexity or peri-OP mortality while it has a potential to increase long term survival.

Methods

We have conducted a retrospective study of 169 patients who underwent a pneumonectomy for NSCLC between January 2005 to December 2015 and focused on stage IIIa patients; a cohort of 51 patients, 30 which received neo adjuvant chemo-radiation (NA group) prior to pneumonectomy and 21 patients who had undergone pneumonectomy followed by adjuvant treatment (Adjuvant group). Surgical complexity and short- and long-term survival were evaluated. Surgical complexity was assessed by surrogates as surgery duration, hospitalization length and interdepartmental transfer.

Results

While no statistically significant differences were found in surgery duration, hospitalization length, morbidity in the 1st year post-OP and the peri-OP mortality; The long term beneficiary effect among the neo adjuvant patients was clear; while 30% of the NA patients were alive 8 years post-OP, there were no survivors in the adjuvant group 5.5 years post-OP.

Conclusion

We conclude that while NA treatment has no effect on operation complexity, peri-OP mortality or post-OP morbidity; its impact on long term survival is protuberant, therefore, we believe that NA treatment should be considered as the treatment of choice in advanced NSCLC in need for pneumonectomy.

PARP-1 inhibition protects the diabetic heart through activation of SIRT1-PGC-1α axis

Type 2 diabetes mellitus (DM2) follows impaired glucose tolerance in obesity and is frequently associated with hypertension, causing adverse myocardial remodelling and leading to heart failure. The DNA bound protein PARP (poly ADP ribose) polymerase catalyses a post translational modification (polymerization of negatively charged ADP-ribose chains) of nuclear proteins. PARP-1 activation is NAD⁺ dependent and takes part in DNA repair and in chromatin remodelling and has a function in transcriptional regulation, intracellular trafficking and energy metabolism. PARP-1 is activated in diabetic cardiomyopathy. We hypothesized that PARP-1 inhibition in diabetic mice may protect cardiomyocytes from inflammation and ROS production.

METHODS

Obese Leptin resistant (db/db) mice suffering from DM2, were treated with angiotensin II (AT) for 4 weeks to enhance the development of cardiomyopathy. Mice were concomitantly treated with the PARP-1 inhibitor INO1001. Neonatal cardiomyocytes exposed to high levels of glucose (33 mM) with or without AT were treated with INO1001. or with SIRT inhibitor (EX-527) in the presence of INO1001 were tested in-vitro.

RESULTS

The in-vivo tests show that hearts from AT treated DM2 mice exhibited cardiac hypertrophy, fibrosis and an increase in the inflammatory marker TNFα. DM2 mice had an increased oxidative stress, concomitant with elevated PARP-1 activity and reduced Sirtuin-1 (SIRT1) expression. PARP-1 inhibition led to increased SIRT1 and Peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α) levels, attenuating oxidative stress, inflammation and fibrosis. In-vitro experiments demonstrated that inhibition of PARP-1 in cardiomyocytes exposed to high levels of glucose and AT led to a significant reduction in ROS (P < 0.01), which was abolished in the presence of the SIRT1 inhibitor together with increased protein expression of SIRT1 and PGC-1α.

CONCLUSION

PARP1 inhibitor INO1001 attenuated cardiomyopathic features in diabetic mice through the activation of SIRT1 and its downstream antioxidant defence mechanisms. The results of this study suggest a pivotal role of PARP-1 inhibition in treating diabetic and AT-induced cardiomyopathy.

Regulation of diabetic cardiomyopathy by caloric restriction is mediated by intracellular signaling pathways involving 'SIRT1 and PGC-1α'

Background

Metabolic disorders such as obesity, insulin resistance and type 2 diabetes mellitus (DM2) are all linked to diabetic cardiomyopathy that lead to heart failure. Cardiomyopathy is initially characterized by cardiomyocyte hypertrophy, followed by mitochondrial dysfunction and fibrosis, both of which are aggravated by angiotensin. Caloric restriction (CR) is cardioprotective in animal models of heart disease through its catabolic activity and activation of the expression of adaptive genes. We hypothesized that in the diabetic heart; this effect involves antioxidant defenses and is mediated by SIRT1 and the transcriptional coactivator PGC-1α (Peroxisome proliferator-activated receptor-γ coactivator).

Methods

Obese Leptin resistant (db/db) mice characterized by DM2 were treated with angiotensin II (AT) for 4 weeks to enhance the development of cardiomyopathy. Mice were concomitantly either on a CR diet or fed ad libitum. Cardiomyocytes were exposed to high levels of glucose and were treated with EX-527 (SIRT1 inhibitor). Cardiac structure and function, gene and protein expression and oxidative stress parameters were analyzed.

Results

AT treated db/db mice developed cardiomyopathy manifested by elevated levels of serum glucose, cholesterol and cardiac hypertrophy. Leukocyte infiltration, fibrosis and an increase in an inflammatory marker (TNFα) and natriuretic peptides (ANP, BNP) gene expression were also observed. Oxidative stress was manifested by low SOD and PGC-1α levels and an increase in ROS and MDA. DM2 resulted in ERK1/2 activation. CR attenuated all these deleterious perturbations and prevented the development of cardiomyopathy. ERK1/2 phosphorylation was reduced in CR mice (p = 0.008). Concomitantly CR prevented the reduction in SIRT activity and PGC-1α (p < 0.04). Inhibition of SIRT1 activity in cardiomyocytes led to a marked reduction in both SIRT1 and PGC-1α. ROS levels were significantly (p < 0.03) increased by glucose and SIRT1 inhibition.

Conclusion

In the current study we present evidence of the cardioprotective effects of CR operating through SIRT1 and PGC-1 α, thereby decreasing oxidative stress, fibrosis and inflammation. Our results suggest that increasing SIRT1 and PGC-1α levels offer new therapeutic approaches for the protection of the diabetic heart.

[EXTRACORPOREAL MEMBRANE OXYGENATION IN ISRAEL: 6.5 YEARS OF EXPERIENCE AT THE LARGEST ECMO TREATMENT CENTER IN ISRAEL]

AIMS

The primary purpose of the study is to evaluate the characteristics of the population treated with ECMO at Beilinson Hospital, the treatment results and a comparison of results with ECMO centers in the world. The treatment outcomes relative to the experience of the team during the years 2008-2014 were also examined. The secondary purpose of this article is to increase the awareness of the medical staff to ECMO as a treatment option for patients with appropriate indications, where indications have increased in recent years.

BACKGROUND

In recent years, there has been a significant increase in extracorporeal life support as a substitute for cardiac function (VA-ECMO) and lung function (VV-ECMO) in light of technological improvements and the experience of the medical teams. The most significant increase in the use of ECMO as a replacement lung function began after the publication of the CESAR study in 2009, which demonstrated a decrease in mortality of patients with acute respiratory distress syndrome treated with ECMO, compared with conservative treatment. Furthermore, during the H1N1 epidemic in 2009-10, a number of observational studies reported good results with the use of ECMO in patients with severe respiratory insufficiency.

METHODS

A retrospective gathering of information, during the period August 2008 to December 2014. Results: During this time, a total of 171 patients were connected to ECMO, 128 patients were connected to AV-ECMO and 43 patients were connected to VV-ECMO. The main causes of respiratory failure were pneumonia (mostly viral) and ARDS; 60% of patients with respiratory failure were successfully weaned from ECMO, and 51% in total were released from intensive care; 71% of patients treated with VA-ECMO were successfully weaned, and 58% in total were released from intensive care. During the six years in which the survey was conducted there was an improvement in patient survival. In 2009 only a third of the patients were released from intensive care, while in 2014 over 71% were discharged.

DISCUSSION

This study reports for the first time on the morbidity characteristics, type of ECMO used and the results of all patients receiving treatment with ECMO in an intensive care unit at a tertiary hospital in Israel. The number of cases treated with ECMO is on the rise in recent years, both globally and in Israel, with good results. Therefore, this treatment option for patients with severe respiratory and/or cardiac insufficiency should be considered as a therapeutic option in appropriate situations.

Early Referral to Coronary Artery Bypass Grafting Following Acute Coronary Syndrome, Trends and Outcomes from the Acute Coronary Syndrome Israeli Survey (ACSIS) 2000-2010

BACKGROUND

Limited information exists on whether changes in medical practices over the study decades have affected the outcomes of acute coronary syndrome (ACS) patients who undergo early coronary artery bypass surgery (CABG) during index hospitalisation.

METHODS

Data on trends for early CABG referral and associated outcomes were obtained among 11,485 ACS patients enrolled in the biennial Acute Coronary Syndrome Israeli Surveys (ACSIS) 2000-2010.

RESULTS

Among 11,485 patients, 566 (5%) were referred to early CABG. These patients displayed higher risk characteristics, including Killip class >II, anterior myocardial infarction, greater left ventricular dysfunction, and more frequent use of mechanical ventilation and intra-aortic balloon pump (all p<0.01). Nevertheless, mortality rates of patients referred to early CABG vs. treated with percutaneous coronary intervention (PCI) or medically, was similar (11.4% vs. 10.2%; log-rank p-value=0.40). There was a significant decline in the referral trend over the study decade (6.7% - 1.7%; p<0.001). One year survival was similar between patients referred to early CABG during the late (years: 2006-2010) vs. early (years: 2000-2005) period (85.7% vs. 90%; log-rank p-value=0.15), whereas, among patients who didn't undergo early CABG, and underwent percutaneous coronary intervention (PCI) or medical management only, enrolment during the late periods was associated with a significant survival benefit (91.5% vs. 88.1%; log-rank p-value<0.001).

CONCLUSIONS

Over the study decade there was a significant decline in referral for early CABG, without a difference in the one-year mortality between the early and non-early CABG group.

Caloric restriction ameliorates cardiomyopathy in animal model of diabetes

BACKGROUND

The db/db mouse is an animal model of diabetes in which leptin receptor activity is deficient resulting accelerated cardiomyopathy when exposed to angiotensin (AT). Toll-like receptors 4 and 2 (TLR4, TLR2) are pattern recognition receptors, that recognize pathogen-associated molecular patterns and exacerbate and release inflammatory cytokines. Fetuin A (Fet A) is a fatty acid carrier which affects inflammation and insulin resistance in obese humans and animals through TLRs. The aim of this study was to investigate the effect of caloric restriction (CR) on free fatty acids (FFA) level and the inflammatory response in diabetic cardiomyopathy.

METHODS AND RESULTS

Left ventricular hypertrophy, increased fibrosis and leukocytes infiltration were observed in db/db AT treated hearts. Serum glucose, FFA, and cholesterol levels were elevated in db/db AT treated mice. Cardiac expression of PPARα increased while AKT phosphorylation was decreased.

CONCLUSIONS

Cumulatively, CR elevated cardiac PPARα improved the utilization of fatty acids, and reduced myocardial inflammation as seen by reduced levels of Fet A. Thus CR negated cardiomyopathy associated with AT in an animal model of diabetes suggesting that CR is an effective therapeutic approach in the treatment of diabetes and associated cardiomyopathy.

Abstract P173: Caloric Restriction Attenuates Diabetic Cardiomyopathy Through the Recruitment of the Antioxidant System

Introduction: Insulin resistance negatively impacts the diabetic heart in various ways, that include impaired insulin-mediated glucose uptake and a reduction in intracellular signalling. Diabetic cardiomyopathy is independent of coronary artery disease and is characterized by increased oxidative stress and extensive fibrotic changes, leading to increased myocardial stiffness and the development of diastolic dysfunction. Caloric restriction (CR) is cardioprotective mainly through its catabolic activity and increased insulin sensitivity. We examined the effect of CR on the development of diabetic cardiomyopathy and changes in oxidative stress and antioxidant genes.

Methods: Leptin resistant (db/db) mice suffer from obesity and diabetes. Mice were treated for 4 weeks with angiotensin II (AT) to induce severe cardiomyopathy. Mice under CR were fed 90% of their normal food intake for 2 weeks and 65% for an additional 2 weeks. Each group consisted of 5-6 animals.

Results: CR attenuated obesity and the cardiomyopathy phenotype in diabetic mice. CR reduced body weight and heart weight in diabetic mice when compared to control animals (33.7±7.9g vs.44 ±5.9g; 0.137±0.023g vs. 0.17±0.02g respectively, p<0.05); and lowered blood glucose (576±167mg/dL vs 702.5±309 mg/dL, p<0.05). Echocardiography indicated that CR attenuated the hypertrophic phenotype in the diabetic mice when compared to control animals (LV internal diameter 3.34±0.46mm vs. 4.06±0.36mm, p<0.01). Diabetic mice treated with AT suffer from oxidative stress as evident in a 110% increase in serum MDA levels (p<0.011), a reduction of 81% in adiponectin (p<0.001) and 65% in PGC-1α (p<0.0046) mRNA levels in cardiac tissue of diabetic mice compared to WT mice. The attenuation of diabetic cardiomyopathy after CR was accompanied by a reduction in serum MDA levels (p<0.028) and an increase in cardiac adiponectin, HO-1 and PGC-1α levels (p<0.05).

Conclusion: These results indicate that a short term CR attenuated the development of AT induced diabetic cardiomyopathy through the activation of the adiponectin- PGC-1α- HO-1-axis. This appears to be a critical module in protecting the diabetic heart from the development of cardiomyopathy.

Silencing cardiomyocyte TLR4 reduces injury following hypoxia

Toll-like receptor 4 (TLR4), the receptor for lipopolysaccharide (LPS) of gram-negative pathogens expressed in the heart, is activated by several endogenous ligands associated with tissue injury in response to myocardial infarction (MI). The aim of this study was to investigate the involvement of TLR4 signaling in cardiomyocytes dysfunction following hypoxia (90min) using multiple methodologies such as knocking down TLR4 and small interfering RNA (siTLR4). Cardiomyocytes of C57Bl/6 mice (WT) subjected to hypoxic stress showed increased cardiac release of LDH, HMGB1, IκB, TNF-α and myocardial apoptotic and necrotic markers (BAX, PI) compared to TLR4 knock out mice (TLR4KO). Treating these cardiomyocytes with siRNA against TLR4 decreased the damage markers (LDH, IκB, TNF-α). TLR4 silencing during hypoxic stress resulted in the activation of the p-AKT and p-GSK3β (by ∼25%). The latter is an indicator that there is a reduction of mitochondrial permeability transition pore (mPTP) opening following hypoxic myocardial induced injury leading to preserved mitochondrial membrane potential. Silencing TLR4 in cardiomyocytes improved cell survival following hypoxic injury through activation of the AKT/GSK3β pathway, reduced inflammatory and apoptotic signals. These findings suggest that TLR4 may serve as a potential target in the treatment of ischemic myocardial injury. Moreover, RNA interfering targeting TLR4 expression represents a therapeutic strategy.

TLR4 Expression Is Associated with Left Ventricular Dysfunction in Patients Undergoing Coronary Artery Bypass Surgery

INTRODUCTION

Toll-like receptor 4 (TLR4) is an innate immune receptor expressed in immune cells and the heart. Activation of the immune system following myocardial ischemia causes the release of proinflammatory mediators that may negatively influence heart function.

AIM

The aim of this study is to determine whether TLR4 is activated in peripheral monocytes and heart tissue taken from patients with varying degrees of myocardial dysfunction caused by coronary artery diseases and scheduled for coronary artery bypass graft (CABG) surgery before 12 months following operation.

METHODS AND RESULTS

Patients (n = 44) undergoing CABG surgery having left ventricular ejection fraction ≤ 45% ('reduced EF', n = 20) were compared to patients with preserved EF >45% ('preserved EF' group, n = 24). 'Reduced EF' patients exhibited increased TLR4 expression in monocytes (2.78±0.49 vs. 1.76±0.07 rMFI, p = 0.03). Plasma levels of C-reactive protein, microRNA miR-320a, brain natriuretic peptide (pro BNP) and NADPH oxidase (NOX4) were also significantly different between the 'preserved EF' and 'reduced EF'groups. Elevated TLR4 gene expression levels in the right auricle correlated with those of EF (p<0.008), NOX4 (p<0.008) and miR320, (p<0.04). In contrast, no differences were observed in peripheral monocyte TLR2 expression. After CABG surgery, monocyte TLR4 expression decreased in all patients, reaching statistical significance in the 'reduced EF' group.

CONCLUSION

TLR4 is activated in peripheral monocytes and heart tissue obtained from patients with ischemic heart disease and reduced left ventricular function. Coronary revascularization decreases TLR4 expression. We therefore propose that TLR4 plays a pathogenic role and may serve as an additional marker of ischemic myocardial dysfunction.

Heme oxygenase-1 induction improves cardiac function following myocardial ischemia by reducing oxidative stress

Background

Oxidative stress plays a key role in exacerbating diabetes and cardiovascular disease. Heme oxygenase-1 (HO-1), a stress response protein, is cytoprotective, but its role in post myocardial infarction (MI) and diabetes is not fully characterized. We aimed to investigate the protection and the mechanisms of HO-1 induction in cardiomyocytes subjected to hypoxia and in diabetic mice subjected to LAD ligation.

Methods

In vitro: cultured cardiomyocytes were treated with cobalt-protoporphyrin (CoPP) and tin protoporphyrin (SnPP) prior to hypoxic stress. In vivo: CoPP treated streptozotocin-induced diabetic mice were subjected to LAD ligation for 2/24 h. Cardiac function, histology, biochemical damage markers and signaling pathways were measured.

Results

HO-1 induction lowered release of lactate dehydrogenase (LDH) and creatine phospho kinase (CK), decreased propidium iodide staining, improved cell morphology and preserved mitochondrial membrane potential in cardiomyocytes. In diabetic mice, Fractional Shortening (FS) was lower than non-diabetic mice (35±1%vs.41±2, respectively p<0.05). CoPP-treated diabetic animals improved cardiac function (43±2% p<0.01), reduced CK, Troponin T levels and infarct size compared to non-treated diabetic mice (P<0.01, P<0.001, P<0.01 respectively). CoPP-enhanced HO-1 protein levels and reduced oxidative stress in diabetic animals, as indicated by the decrease in superoxide levels in cardiac tissues and plasma TNFα levels (p<0.05). The increased levels of HO-1 by CoPP treatment after LAD ligation led to a shift of the Bcl-2/bax ratio towards the antiapoptotic process (p<0.05). CoPP significantly increased the expression levels of pAKT and pGSK3β (p<0.05) in cardiomyocytes and in diabetic mice with MI. SnPP abolished CoPP's cardioprotective effects.

Conclusions

HO-1 induction plays a role in cardioprotection against hypoxic damage in cardiomyocytes and in reducing post ischemic cardiac damage in the diabetic heart as proved by the increased levels of pAKT with a concomitant inhibition of pGSK3β leading to preserved mitochondrial membrane potential.

Tricuspid valve replacement: the effect of gender on operative results

BACKGROUND AND AIM OF THE STUDY

Tricuspid valve replacement (TVR) is considered a high-risk operation. The study aim was to analyze the authors' eight-year experience with TVR and to characterize the specific risk factors for this operation.

METHODS

Between January 2005 and August 2012, a total of 67 patients (46 females, 21 males; mean age 58 +/- 14 years; range: 25-86 years) underwent TVR at the authors' center. Re-do operations were performed in 48 patients (72%), including 37 patients (55%) who had at least two previous surgeries. Isolated TVR was performed in 28 patients (42%). The follow up (mean 28 months) included echocardiography and survival analysis.

RESULTS

The overall operative mortality was 17.9% (n = 12, all female). In the latter half of the study period, mortality declined to 11.4% (p = NS). Major postoperative morbidity included prolonged mechanical ventilation (28.4%), low cardiac output (29.8%), and acute renal failure requiring hemodialysis (10.4%). Univariate analysis revealed that female gender (p = 0.007), NYHA class (p = 0.038), serum bilirubin level (p = 0.02) and number of previous cardiac surgeries (p = 0.05) were associated with increased operative mortality. Multivariable analysis demonstrated that reoperation (OR 6.06, p = 0.036) was an independent risk factor for operative mortality or complications. Echocardiography at follow up showed that 92.6% of all patients had tricuspid regurgitation grade < 2. The overall five-year survival rates for males and females were 82% and 53%, respectively (p = 0.03), but five-year survival for operative survivors was similar in males and females (82% versus 73%, p = 0.5). Cox regression analysis showed that age (OR 1.07, p = 0.028) and reoperation (OR 6.1, p = 0.038) were independent risk factors for late mortality.

CONCLUSION

TVR remains a high-risk operation, particularly for advanced age and previously operated patients; however, the long-term survival is satisfactory. Typically, women undergo TVR at an older age with a higher mortality rate than men. However, the long-term mortality rate of patients who survived surgery was not associated with gender.

The role of mutant protein level in autosomal recessive catecholamine dependent polymorphic ventricular tachycardia (CPVT2)

Humans and genetically engineered mice with recessively inherited CPVT develop arrhythmia which may arise due to malfunction or degradation of calsequestrin (CASQ2). We investigated the relation between protein level and arrhythmia severity in CASQ2(D307H/D307H) (D307H), compared to CASQ2(Δ/Δ) (KO) and wild type (WT) mice. CASQ2 expression and Ca²⁺ transients were recorded in cardiomyocytes from neonatal or adult mice. Arrhythmia was studied in vivo using heart rhythm telemetry at rest, exercise and after epinephrine injection. CASQ2 protein was absent in KO heart. Neonatal D307H and WT hearts expressed significantly less CASQ2 protein than the level found in the adult WT. Adult D307H expressed only 20% of CASQ2 protein found in WT. Spontaneous Ca²⁺ release was more prevalent in neonatal KO cardiomyocytes (89%) compared to 33-36% of either WT or D307H, respectively, p<0.001. Adult cardiomyocytes from both mutant mice had more Ca²⁺ abnormalities compared to control (KO: 82%, D307H 63%, WT 12%, p<0.01). Calcium oscillations were most common in KO cardiomyocytes. We then treated mice with bortezomib to inhibit CASQ2(D307H) degradation. Bortezomib increased CASQ2 expression in D307H hearts by ∼50% (p<0.05). Bortezomib-treated D307H mice had lower CPVT prevalence and less premature ventricular beats during peak exercise. No benefit against arrhythmia was observed in bortezomib treated KO mice. These results indicate that the mutant CASQ2(D307H) protein retains some of its physiological function. Its expression decreases with age and is inversely related to arrhythmia severity. Preventing the degradation of mutant protein should be explored as a possible therapeutic strategy in appropriate CPVT2 patients.

Infarct-induced steroidogenic acute regulatory protein: a survival role in cardiac fibroblasts

Steroidogenic acute regulatory protein (StAR) is indispensable for steroid hormone synthesis in the adrenal cortex and the gonadal tissues. This study reveals that StAR is also expressed at high levels in nonsteroidogenic cardiac fibroblasts confined to the left ventricle of mouse heart examined 3 days after permanent ligation of the left anterior descending coronary artery. Unlike StAR, CYP11A1 and 3β-hydroxysteroid dehydrogenase proteins were not observed in the postinfarction heart, suggesting an apparent lack of de novo cardiac steroidogenesis. Work with primary cultures of rat heart cells revealed that StAR is induced in fibroblasts responding to proapoptotic treatments with hydrogen peroxide or the kinase inhibitor staurosporine (STS). Such induction of StAR in culture was noted before spontaneous differentiation of the fibroblasts to myofibroblasts. STS induction of StAR in the cardiac fibroblasts conferred a marked resistance to apoptotic cell death. Consistent with that finding, down-regulation of StAR by RNA interference proportionally increased the number of STS-treated apoptotic cells. StAR down-regulation also resulted in a marked increase of BAX activation in the mitochondria, an event known to associate with the onset of apoptosis. Last, STS treatment of HeLa cells showed that apoptotic demise characterized by mitochondrial fission, cytochrome c release, and nuclear fragmentation is arrested in individual HeLa cells overexpressing StAR. Collectively, our in vivo and ex vivo evidence suggests that postinfarction expression of nonsteroidogenic StAR in cardiac fibroblasts has novel antiapoptotic activity, allowing myofibroblast precursor cells to survive the traumatized event, probably to differentiate and function in tissue repair at the infarction site.

Popeye domain-containing 1 is down-regulated in failing human hearts

Congestive heart failure, a complex disease of heterogeneous etiology, involves alterations in the expression of multiple genes. The Popeye domain-containing (POPDC) family of three novel muscle-restricted genes (POPDC1-3) is evolutionarily conserved and developmentally regulated. In mice, POPDC1 has been shown to play an important role in skeletal and cardiac muscles subjected to injury or stress. However, it has never been explored in human hearts. In biopsies from non-failing and failing human hearts, we examined the cellular distribution of POPDC1 as well as the expression patterns of POPDC1-3 mRNAs. POPDC1 was visualized by immunohistochemistry and estimated by Western immunoblotting. The mRNA levels of POPDC1-3 and ß myosin heavy chain (MYHC7) were assessed using reverse transcription/quantitative polymerase chain reaction. POPDC1 was predominantly localized in the sarcolemma with an enhanced expression in the intercalated discs. In failing hearts, many cardiomyocytes appeared deformed and POPDC1 labeling was deranged. The three POPDC mRNAs were expressed in the four heart chambers with higher transcript levels in the ventricles compared to the atria. Heart failure concurred with reduced levels of POPDC1 mRNA and protein in the left ventricle. Correlation analyses of mRNA levels among the failing heart specimens indicated the coordinated regulation of POPDC1 with POPDC3 and of POPDC2 with MYHC7. It can be concluded that POPDC gene expression is modified in end-stage heart failure in humans in a manner suggesting regulatory and/or functional differences between the three family members and that POPDC1 is particularly susceptible to this condition.

Popeye domain-containing 1 is down-regulated in failing human hearts

Congestive heart failure, a complex disease of heterogeneous etiology, involves alterations in the expression of multiple genes. The Popeye domain-containing (POPDC) family of three novel muscle-restricted genes (POPDC1-3) is evolutionarily conserved and developmentally regulated. In mice, POPDC1 has been shown to play an important role in skeletal and cardiac muscles subjected to injury or stress. However, it has never been explored in human hearts. In biopsies from non-failing and failing human hearts, we examined the cellular distribution of POPDC1 as well as the expression patterns of POPDC1-3 mRNAs. POPDC1 was visualized by immunohistochemistry and estimated by Western immunoblotting. The mRNA levels of POPDC1-3 and ß myosin heavy chain (MYHC7) were assessed using reverse transcription/quantitative polymerase chain reaction. POPDC1 was predominantly localized in the sarcolemma with an enhanced expression in the intercalated discs. In failing hearts, many cardiomyocytes appeared deformed and POPDC1 labeling was deranged. The three POPDC mRNAs were expressed in the four heart chambers with higher transcript levels in the ventricles compared to the atria. Heart failure concurred with reduced levels of POPDC1 mRNA and protein in the left ventricle. Correlation analyses of mRNA levels among the failing heart specimens indicated the coordinated regulation of POPDC1 with POPDC3 and of POPDC2 with MYHC7. It can be concluded that POPDC gene expression is modified in end-stage heart failure in humans in a manner suggesting regulatory and/or functional differences between the three family members and that POPDC1 is particularly susceptible to this condition.

Pulmonary venous drainage through a highly vascularized left atrial tumor

We present a patient with symptomatic congestive heart failure due to a left atrial sarcoma infiltrating and apparently occluding the left pulmonary veins. The tumor was highly vascularized and enabled attenuated blood drainage from the left upper and lower pulmonary veins despite intra-operative appearance as completely obliterative, thus avoiding persistent left lung pulmonary edema. The tumor was partially removed and the pathologic findings showed advanced angiogenesis. Malignant tumors may occlude large blood vessels and thus may result in the development of a collateral flow. However, we suggest that highly vascularized tumors (macroscopic totally occlusive) may serve as a sponge and enable attenuated blood flow through the tumor and hence may avoid a complete cut off in blood supply or drainage.

Behçet’s Aortitis Mimicking Aortic Valve Endocarditis with Subaortic Complications

Behçet's disease is a systemic inflammatory disease with rare cardiac involvement. We present a case of Behçet's aortitis involving the aortic and mitral valves with vegetations resembling aortic valve endocarditis with subaortic complications. Recurrent aortitis after aortic valve replacement resulted in an aortic pseudoaneurysm formation with moderate perivalvular aortic regurgitation that stabilized with immunosuppressive therapy and without the need for additional cardiac operation.