Comparison of de novo implantation vs. upgrade cardiac resynchronisation therapy: a multicentre experience

BACKGROUND

The clinical safety and consequences of upgrade procedures compared with de novo cardiac resynchronisation therapy (CRT) implantation in heart failure remain unclear. The present study aimed to assess clinical and procedural consequences of patients undergoing CRT upgrade as compared to de novo CRT implantations.

METHODS

In this prospective cohort study, two subgroups were considered as the study population as (1) de novo group that CRT was considered on optimised medical treatment with heart failure of NYHA functional class from II to IV, left ventricular ejection fraction (LVEF) of ≤35%, and QRS width of >130 ms and (2) upgrade group including the patients with previously implantable cardioverter defibrillator (ICD) with the indications for upgrading to CRT. The two groups were compared regarding the changes in clinical outcome and echocardiography parameters.

RESULTS

The procedure was successful in 95.9% of patients who underwent CRT upgrade and 100% of those who underwent de novo CRT implantation. It showed a significant improvement in LVEF, severity of mitral regurgitation and NYHA functional classification, without any difference between the two study groups. Overall procedural related complications were reported in 10.8% and 3.8% (p = .093) and cardiac death in 5.4% and 2.5% (p = .360), respectively, with no overall difference in postoperative outcome between the two groups.

CONCLUSIONS

Upgrading to CRT is a safe and effective procedure regarding improvement of functional class, left ventricular function status and post-procedural outcome.

Clinical outcomes of subcutaneous implantable cardiac defibrillator implantation - Iran SICD registry

BACKGROUND

The subcutaneous implantable-defibrillator (S-ICD) is a relatively new alternative to the transvenous ICD system to minimize intravascular lead-related complications. This paper presents outcome of SICD implantation in patients enrolled in Iran S-ICD registry.

METHODS

Between October 2015 and June 2022, this prospective multicenter national registry included 223 patients with a standard indication for an ICD, who neither required bradycardia pacing nor needed cardiac resynchronization to evaluate the early post-implant complications and long-term follow-up results of the S-ICD system.

RESULTS

The mean age of the patients was 45 ± 17 years. The majority (79.4%) were male. Ischemic cardiomyopathy (39.5%) was the most common underlying disorder among patients selected for S-ICD implant. Most study patients (68.6%) had ICD for primary prevention of sudden cardiac death. Seven patients (3.1%) were found to have suboptimal lead positions. Six patients (2.7%) developed a pocket hematoma; all were managed medically. During a mean follow-up of 2 years, the appropriate therapy was recorded in 13% of the patients and inappropriate ICD intervention mainly due to supraventricular tachycardia in 8.9%. Pocket infection was observed in four patients (1.8%) and five patients (2.2%) died mainly due to heart failure.

CONCLUSION

S-ICDs were effective at detecting and treating both induced and spontaneous ventricular arrhythmias. Major clinical complications were rare.

Genetic Insights from Consanguineous Cardiomyopathy Families

Inherited cardiomyopathies are a prevalent cause of heart failure and sudden cardiac death. Both hypertrophic (HCM) and dilated cardiomyopathy (DCM) are genetically heterogeneous and typically present with an autosomal dominant mode of transmission. Whole exome sequencing and autozygosity mapping was carried out in eight un-related probands from consanguineous Middle Eastern families presenting with HCM/DCM followed by bioinformatic and co-segregation analysis to predict the potential pathogenicity of candidate variants. We identified homozygous missense variants in TNNI3K, DSP, and RBCK1 linked with a dilated phenotype, in NRAP linked with a mixed phenotype of dilated/hypertrophic, and in KLHL24 linked with a mixed phenotype of dilated/hypertrophic and non-compaction features. Co-segregation analysis in family members confirmed autosomal recessive inheritance presenting in early childhood/early adulthood. Our findings add to the mutational spectrum of recessive cardiomyopathies, supporting inclusion of KLHL24, NRAP and RBCK1 as disease-causing genes. We also provide evidence for novel (recessive) modes of inheritance of a well-established gene TNNI3K and expand our knowledge of the clinical heterogeneity of cardiomyopathies. A greater understanding of the genetic causes of recessive cardiomyopathies has major implications for diagnosis and screening, particularly in underrepresented populations, such as those of the Middle East.

Cardiomyopathy with lethal arrhythmias associated with inactivation of KLHL24

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiovascular disorder, yet the genetic cause of up to 50% of cases remains unknown. Here, we show that mutations in KLHL24 cause HCM in humans. Using genome-wide linkage analysis and exome sequencing, we identified homozygous mutations in KLHL24 in two consanguineous families with HCM. Of the 11 young affected adults identified, 3 died suddenly and 1 had a cardiac transplant due to heart failure. KLHL24 is a member of the Kelch-like protein family, which acts as substrate-specific adaptors to Cullin E3 ubiquitin ligases. Endomyocardial and skeletal muscle biopsies from affected individuals of both families demonstrated characteristic alterations, including accumulation of desmin intermediate filaments. Knock-down of the zebrafish homologue klhl24a results in heart defects similar to that described for other HCM-linked genes providing additional support for KLHL24 as a HCM-associated gene. Our findings reveal a crucial role for KLHL24 in cardiac development and function.

Menopause knowledge and attitude among Iranian women

Objective: The present study was done to assess the effects of training on knowledge and attitude level promotion of post menopause women about menopause. Methods & Material: The research communication included 100 menopausal women aged 45-60 years, who were selected in a stratified manner (according to the economic status: poor, average, and good). The tool used was an examiners-made questionnaire, which contained 3 parts: demographic characteristics, knowledge and attitude measurement. Results: Eleven percent of the studied women had a low knowledge regarding menopause and 1% was good. After training, 27% got a good knowledge and no one remained at the low level. The attitude of 59% of the studied women regarding menopause was positive and 80% got a positive attitude after training. A significant relation was found between knowledge and attitude, before and after training. Conclusion: Despite the fact that the majority of women judge menopause as a positive incident, it seems that paying attention to their training caused the bringing to their knowledge of the natural menopause and having a healthy and jolly life.

Clinical value and severity of myocardial perfusion defects in asymptomatic diabetic patients with negative or weakly positive exercise treadmill test

Objective:

Although coronary artery disease (CAD) is the leading cause of death in type 2 diabetic patients, it is frequently asymptomatic. Myocardial perfusion imaging (MPI) is reported to show ischemia in a significant number of asymptomatic diabetic patients. We studied the prevalence and severity of myocardial perfusion defects in asymptomatic diabetic patients and its clinical impact.

Methods and patients:

One hundred thirty consecutive asymptomatic patients, aged 35-65 years with type 2 diabetes mellitus and with no history of CAD and no cardiac symptoms were recruited in the study. Echocardiography, electrocardiography (ECG), routine laboratory tests and exercise treadmill test (ETT) were performed and patients with weakly positive or negative ETT underwent Dipyridamole MPI. Patients with positive ETT were referred to coronary angiography. Patients were followed for at least 17 months (mean 21.7 months) and any cardiac event was recorded.

Results:

We studied 81 female and 49 male patients with mean age of 51.8 years. Negative, weakly positive and positive ETT result was noted in 74.3%, 15% and 10.7% respectively. 75% of patients with positive ETT had coronary artery disease in angiography. Gated myocardial perfusion SPECT was done in 106 patients. MPI showed reversible defect in 26.9% of the patients with a mean summed stress score of 3.3±1.8. Follow up completed in 112 patients and only one patient with abnormal MPI underwent coronary angiography followed by PTCA. No cardiac death, MI, UA or hospital admission occurred among our patients during follow up (17-26 months). Mean stress end diastolic volume (EDV) was significantly higher in patients with reversible defect compared to patients without reversible defect based on MPI findings (62.0±31.6 Vs 48.5±18.4 ml, P=0.04). Blood glucose and HbA1c were significantly higher in patients with ischemia compared to patients without ischemia (P<0.05). Meanwhile the ratio of TG to HDL was 6.06±3.2 in ischemic patients compared to 4.8±2.3 in normal subjects (P=0.03).

Conclusion:

Reversible defects are commonly seen in myocardial perfusion SPECT in asymptomatic diabetic patients and are mild in severity and not associated with adverse cardiac events. Routine approach for detection of CAD beginning with ETT seems to be appropriate in these patients.