How variable are the volumetric measurements from gated perfusion SPECT when a one-day stress-rest protocol is used?

BACKGROUND: Using myocardial perfusion scintigraphy (MPS), an increase in left ventricular (LV) volumes or a decrease in ejection fraction (EF) from rest to stress may be clinically important. The variation in these measures between the low-dose stress acquisition and high-dose rest acquisition in a one-day stress-rest protocol has not been established. We assessed the reproducibility of gated volumetric indices between stress and rest and the normal variation in ungated TID ratio for a one-day stress-rest 99mTc-tetrofosmin protocol. METHODS: Two thousand and one hundred and fifty eight (2158) 99mTc-tetrofosmin MPS patient studies were analyzed retrospectively. Studies were excluded for incomplete data, significant technical difficulties, or (for gated analysis but not for analysis of TID ratio) if the LV EF was > 75%. An analysis of gated data was undertaken to establish the reproducibility of ventricular volumes and EF between stress and rest scans. Ungated volume data were analyzed to determine the confidence limits of TID ratio according to ventricular volume. RESULTS: Gated data were analyzed for 621 patients without inducible hypoperfusion. Mean EF at rest was slightly higher than after stress (62.4% ± 10.3% vs 61.2% ± 10.4%, P < 0.001), and the standard deviation of the difference was 5.2% (95% CI 4.9% to 5.5%). Ungated volumes were available for 992 non-ischaemic patients. The upper 95% CI for TID ratio was 1.23. This increased from 1.20 to 1.37 between the highest and lowest deciles of rest ungated volume. CONCLUSION: Using a one-day stress-rest 99mTc-tetrofosmin protocol, a fall in LV EF between rest and stress of > 11.6% or a TID ratio of > 1.23 is likely to be clinically reliable. The upper limit of normal for TID ratio needs to be increased for patients with small LV chamber volumes.

The peer-review process in Europe's leading case report journal for cardiovascular diseases: a survey for improving transparency and quality.

Graphical abstract summarizing main study results.

Independent effects of adiposity measures on risk of atrial fibrillation in men and women: a study of 0.5 million individuals.

BACKGROUND: Atrial fibrillation (AF) has a higher prevalence in men than in women and is associated with measures of adiposity and lean mass (LM). However, it remains uncertain whether the risks of AF associated with these measures vary by sex. METHODS: Among 477 904 UK Biobank participants aged 40-69 without prior AF, 23 134 incident AF cases were identified (14 400 men, 8734 women; median follow-up 11.1 years). Cox proportional hazards models were used to estimate the covariate adjusted hazard ratios (HRs) describing the association of AF with weight, measures of adiposity [fat mass (FM), waist circumference (WC)] and LM, and their independent relevance, by sex. RESULTS: Weight and WC were independently associated with risk of AF [HR: 1.25 (1.23-1.27) per 10 kg, HR: 1.11 (1.09-1.14) per 10 cm, respectively], with comparable effects in both sexes. The association with weight was principally driven by LM, which, per 5 kg, conferred double the risk of AF compared with FM when mutually adjusted [HR: 1.20 (1.19-1.21), HR: 1.10 (1.09-1.11), respectively]; however, the effect of LM was weaker in men than in women (p-interaction = 4.3 x 10-9). Comparing the relative effects of LM, FM and WC identified different patterns within each sex; LM was the strongest predictor for both, whereas WC was stronger than FM in men but not in women. CONCLUSIONS: LM and FM (as constituents of weight) and WC are risk factors for AF. However, the independent relevance of general adiposity for AF was more limited in men than in women. The relevance of both WC and LM suggests a potentially important role for visceral adiposity and muscle mass in AF development.

An assessment of adherence to CARE reporting standards by case reports published in European Heart Journal - Case Reports in 2018.

BACKGROUND: Case reports are subject to significant variation in their content, and the absence of pertinent case details can limit their benefit to the medical community. To aid this, a reporting standard (CARE) has been developed. Case reports published in European Heart Journal - Case reports (EHJ-CR) are subject to specific checks by editors to confirm compliance with the CARE reporting standard. However, a degree to which case reports published by EHJ-CR comply with the CARE reporting standards has not been established. METHODS: Case reports published in EHJ-CR during 2018 were reviewed for compliance with the CARE reporting standards. Two authors assessed each article for compliance with each of the 31 criteria. RESULTS: In 2018, 130 case reports/series were published by EHJ-CR. The median number of CARE criteria achieved by each article was 21 (interquartile range 21-25) out of 31. CARE criteria with the highest adherence were timeline inclusion, a clear and well-referenced discussion, and declaration of competing interests, all present in 100% of articles. In contrast, some aspects were poorly adhered to including patient perspective, and details of funding sources. There was no difference in overall compliance with aspects of the CARE standard between diagnostic and interventional case reports. However, lower compliance was seen for the discussion of diagnostic challenges in interventional studies (19%), when compared to diagnostic studies (44%). The continent of authorship and month submitted did not affect CARE adherence. CONCLUSIONS: There was good compliance with the CARE reporting standards by case reports published in EHJ-CR. A number of specific areas for improvement have been identified which will be considered by the editorial board of EHJ-CR.

Are conflict of interest declarations appropriate to allow sufficient consideration of potential bias in presentations?

BACKGROUND: Potential conflicts of interest (CoI) are common in medical research, necessitating the use of CoI declarations. There is currently no consensus document or external authority guiding CoI declarations in conference settings, resulting in declarations of variable quality and utility. METHODS: We explored four CoI declaration parameters (sufficient slide display time; the presence of any verbal explanation pertaining to relevant CoI; the use of an adequate font size; and whether the nature and relevance of the CoI was described). Parameters were graded from one to three points, with the sum of parameters providing an overall declaration quality out of 12. We then applied this scoring system to recordings of presentations from the British Cardiovascular Society (BCS) annual conference 2018 which were available online. RESULTS: Sixty-nine presentations were suitable for inclusion, of which 47 (68%) contained a CoI statement. Thirty-six of the 47 (77%) presentations declared that they had no CoI. In the remaining 11 (23%) with reported CoI, the median time spent displaying CoI was 1 second (interquartile range (IQR) 0.7-3.3). The median quality score for presentations was 7 (IQR 6-10). CONCLUSION: This study demonstrates utility in considering aspects of CoI declarations at conferences to improve transparency.

Twiddler's syndrome with a subcutaneous implantable cardioverter-defibrillator presenting with an inappropriate shock: a case report.

BACKGROUND: Subcutaneous implantable cardioverter-defibrillators (S-ICDs) are increasingly used in patients at risk of fatal cardiac arrhythmias. Twiddler's syndrome is a condition in which a device is manipulated by the patient after implantation leading to lead twisting and retraction. Device manipulation has been reported multiple times in transvenous pacing systems and occasionally leads to inappropriate discharges from implanted defibrillators. However, little has been reported about device manipulation in S-ICD devices. CASE SUMMARY: We present the case of a 16-year-old who underwent insertion of an S-ICD for idiopathic dilated cardiomyopathy. He represented for a pacing check following a discharge from the device. This showed a significant change in the sensed vectors. Chest radiographs confirmed lead retraction and suggested device manipulation. The device was turned off to prevent further inappropriate shocks. The patient underwent successful reimplantation of a S-ICD device. DISCUSSION: This case highlights that twiddler's syndrome can occur in those with an S-ICD and lead to an inappropriate device discharge. The patient in this case had a number of risk factors that have been previously associated with twiddler's syndrome.

Does YouTube provide high-quality resources for patient education on atrial fibrillation ablation?

OBJECTIVE: Catheter ablation has a role in the treatment of selected patients with atrial fibrillation (AF). Patients are increasingly utilising the internet as an education resource. However, there is limited oversight on online patient information. This study aimed to determine the quality of video-based patient education resources for catheter ablation in AF. METHODS: YouTube was searched for "Ablation" and one of "Atrial Fibrillation" or "AFib" or "AF" (a total of three searches). Videos were included if they discussed catheter ablation and excluded if they primarily discussed surgical/hybrid ablation or were non-English language. Each video was scored by two authors for compliance with a gold-standard item set created from patient booklets from the Arrhythmia Alliance. RESULTS: A total of 6357 videos were identified from all searches. Of these, a total of 111 videos met inclusion criteria and were included in the analysis. The median number of views for each video was 1794.5 (IQR 335 to 10,972) with a median duration of 217 s (IQR 135 to 444 s). The median number of essential criteria found in each video was 4/21 (IQR 3 to 6), and no video met all the essential criteria. Video score was not significantly correlated with video likes or number of views. CONCLUSIONS: No available videos provide sufficiently detailed information for a patient to have a reasonable understanding of catheter ablation. A lack of correlation between views/'likes' and video score suggests patients are unable to critically evaluate these resources for educational content.

Atrial Fibrillation and Anticoagulation in Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) represents a common inherited cardiac disorder with well-known complications Including stroke and sudden cardiac death. There is a recognised association between HCM and the development of AF. This review describes the epidemiology of AF within the HCM population and analyses the risk factors for the development of AF. It further discusses the outcomes associated with AF in this population, including the evidence in support of higher stroke risk in patients with HCM with AF compared with the general AF population. Finally, the evidence and recommendations for anticoagulation in this patient group are addressed.