Persistence of significant secondary mitral regurgitation post-cardiac resynchronization therapy and survival: a systematic review and meta-analysis : Mitral regurgitation and mortality post-CRT.

Cardiac resynchronization therapy (CRT) significantly reduces secondary mitral regurgitation (MR) in patients with severe left ventricular systolic dysfunction. However, uncertainty remains as to whether improvement in secondary MR correlates with improvement with mortality seen in CRT. We conducted a meta-analysis to determine the association of persistent unimproved significant secondary MR (defined as moderate or moderate-to-severe or severe MR) compared to improved MR (no MR or mild MR) post-CRT with all-cause mortality, cardiovascular mortality, and heart failure hospitalization. A systematic search of PubMed, EMBASE, and Cochrane Library databases till July 31, 2022 identified studies reporting clinical outcomes by post-CRT secondary MR status. In 12 prospective studies of 4954 patients (weighted mean age 66.8 years, men 77.8%), the median duration of follow-up post-CRT at which patients were re-evaluated for significant secondary MR was 6 months and showed significant relative risk reduction of 30% compared to pre-CRT. The median duration of follow-up post-CRT for ascertainment of main clinical outcomes was 38 months. The random effects pooled hazard ratio (95% confidence interval) of all-cause mortality in patients with unimproved secondary MR compared to improved secondary MR was 2.00 (1.57-2.55); p < 0.001). There was insufficient data to evaluate secondary outcomes in a meta-analysis, but limited data that examined the relationship showed significant association of unimproved secondary MR with increased cardiovascular mortality and heart failure hospitalization. The findings of this meta-analysis suggest that lack of improvement in secondary MR post-CRT is associated with significantly elevated risk of all-cause mortality and possibly cardiovascular mortality and heart failure hospitalization. Future studies may investigate approaches to address persistent secondary MR post-CRT to help improved outcome in this population.

Evolution and Prognosis of Tricuspid and Mitral Regurgitation Following Cardiac Implantable Electronic Devices. A Systematic Review and Meta-analysis.

BACKGROUND: Significant changes in tricuspid regurgitation (TR) and mitral regurgitation (MR) post-cardiac implantable electronic devices (CIED) are increasingly recognized. However, uncertainty remains as to whether risk of CIED-associated TR and MR differs with right ventricular pacing (RVP) via CIED with trans-tricuspid RV leads, compared to cardiac resynchronization therapy (CRT), conduction system pacing (CSP), and leadless pacing (LP). AIMS: Synthesize extant data on risk and prognosis of significant post-CIED TR and MR across pacing strategies. METHODS: We searched PubMed, EMBASE, and Cochrane Library databases published until October 31st, 2023. Significant post-CIED TR and MR were defined as ≥ moderate. RESULTS: Fifty-seven TR studies (N=13,723 patients) and 90 MR studies (N =14,387 patients) were included. For all CIED, risk of post-CIED TR increased (pooled odds ratio (OR)=2.46 and 95% CI=1.88-3.22), while risk of post-CIED MR reduced (OR=0.74, 95% CI=0.58-0.94) after 12 and 6 months of median follow-up respectively. RVP via CIED with trans-tricuspid RV leads was associated with increased risk of post-CIED TR (OR=4.54, 95% CI=3.14-6.57) and post-CIED MR (OR=2.24, 95% CI=1.18-4.26). Binarily, CSP did not alter TR risk (OR=0.37, 95% CI=0.13-1.02), but significantly reduced MR (OR =0.15, 95% CI=0.03-0.62). CRT did not significantly change TR risk (OR=1.09, 95% CI=0.55-2.17), but significantly reduced MR with prevalence pre-CRT of 43%, decreasing post-CRT to 22% (OR =0.49, 95% CI=0.40-0.61). There was no significant association of LP with post-CIED TR (OR=1.15, 95% CI=0.83-1.59) or MR (OR=1.31, 95% CI=0.72-2.39). CIED-associated TR was independently predictive of all-cause mortality (pooled hazard ratio (HR)=1.64, 95% CI=1.40-1.90) after median of 53 months. MR persisting post-CRT independently predicted all-cause mortality (HR=2.00, 95% CI=1.57-2.55) after 38 months. CONCLUSIONS: Our findings suggest that, when possible, adoption of pacing strategies which avoid isolated trans-tricuspid RV leads may be beneficial in preventing incident or deteriorating atrioventricular valvular regurgitation and might reduce mortality.

Risk of ventricular arrhythmia in cardiac resynchronization therapy responders and super-responders: a systematic review and meta-analysis.

AIMS: Response to cardiac resynchronization therapy (CRT) is associated with improved survival, and reduction in heart failure hospitalization, and ventricular arrhythmia (VA) risk. However, the impact of CRT super-response [CRT-SR, increase in left ventricular ejection fraction (LVEF) to ≥ 50%] on VA remains unclear. METHODS AND RESULTS: We undertook a meta-analysis aimed at determining the impact of CRT response and CRT-SR on risk of VA and all-cause mortality. Systematic search of PubMed, EMBASE, and Cochrane databases, identifying all relevant English articles published until 31 December 2019. A total of 34 studies (7605 patients for VA and 5874 patients for all-cause mortality) were retained for the meta-analysis. The pooled cumulative incidence of appropriate implantable cardioverter-defibrillator therapy for VA was significantly lower at 13.0% (4.5% per annum) in CRT-responders, vs. 29.0% (annualized rate of 10.0%) in CRT non-responders, relative risk (RR) 0.47 [95% confidence interval (CI) 0.39-0.56, P < 0.0001]; all-cause mortality 3.5% vs. 9.1% per annum, RR of 0.38 (95% CI 0.30-0.49, P < 0.0001). The pooled incidence of VA was significantly lower in CRT-SR compared with CRT non-super-responders (non-responders + responders) at 0.9% vs. 3.8% per annum, respectively, RR 0.22 (95% CI 0.12-0.40, P < 0.0001); as well as all-cause mortality at 2.0% vs. 4.3%, respectively, RR 0.47 (95% CI 0.33-0.66, P < 0.0001). CONCLUSIONS: Cardiac resynchronization therapy super-responders have low absolute risk of VA and all-cause mortality. However, there remains a non-trivial residual absolute risk of these adverse outcomes in CRT responders. These findings suggest that among CRT responders, there may be a continued clinical benefit of defibrillators.

The role of coronary artery calcification testing in incident coronary artery disease risk prediction in type 1 diabetes.

AIMS/HYPOTHESIS: We sought to assess the role of coronary artery calcification (CAC) and its progression in predicting incident coronary artery disease (CAD) in individuals with type 1 diabetes using data from the Pittsburgh Epidemiology of Diabetes Complications (EDC) Study. METHODS: The present study examined 292 participants who had at least one CAC measure and were free from CAD at baseline; 181 (62%) had repeat CAC assessments 4-8 years later and did not develop CAD between the two CAC measures. The HRs of incident CAD events were estimated using Cox models in categorised or in appropriately transformed CAC scores. C statistics and net reclassification improvement (NRI) were used to assess the added predictive value of CAC for incident CAD. RESULTS: At baseline, the mean age of participants was 39.4 years and the mean diabetes duration was 29.5 years. There were 76 participants who experienced a first incident CAD event over an average follow-up of 10.7 years. At baseline, compared with those without CAC (Agatston score = 0), the adjusted HR (95% CI) in groups of 1-99, 100-399 and ≥400 was 3.1 (1.6, 6.1), 4.4 (2.0, 9.5) and 4.8 (1.9, 12.0), respectively. CAC density was inversely associated with incident CAD in those with CAC volume ≥100 (HR 0.3 [95% CI 0.1, 0.9]) after adjusting for volume score. Among participants with repeated CAC measures, annual CAC progression was positively associated with incident CAD after controlling for baseline CAC. The HR (95% CI) for above vs below the median annual CAC volume progression was 3.2 (1.2, 8.5). When compared with a model that only included established risk factors, the addition of CAC improved the predictive ability for incident CAD events in the whole group. CONCLUSIONS/INTERPRETATION: CAC is strongly associated with incident CAD events in individuals with type 1 diabetes; its inclusion in CAD risk models may lead to improvement in prediction over established risk factors.

Ongoing Risk of Ventricular Arrhythmias and All-Cause Mortality at Implantable Cardioverter Defibrillator Generator Change: A Systematic Review and Meta-Analysis.

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A case of shigellosis with intractable septic shock and convulsions.

Although shigellosis is a potentially fatal disease that may cause a number of extra-intestinal manifestations, intractable septic shock is an unusual complication. Here we describe a 6-month-old infant who developed severe septic shock and convulsions during an episode of dysentery caused by multidrug-resistant Shigella dysenteriae. The case presentation demonstrates how shigellosis can lead to rare and potentially misleading complications such as septic shock when not treated adequately and promptly.