AbstractIntroductionMyocardial infarction (MI) is associated with an increase in subsequent heart failure (HF), recurrent ischemic events, sudden cardiac arrest, and ventricular arrhythmias (SCA‐VA). The primary objective of the study to determine the role of intercurrent HF and ischemic events on the development of SCA‐VA following first type I MI.Methods and resultsA retrospective cohort study of patients experiencing first type 1 MI in Olmsted County, Minnesota (2002‐2012) was conducted by identifying patients using the medical records linkage system (Rochester epidemiology project). Patients aged ≥18 years were followed from the time of MI till death or 31 July, 2017. Intercurrent HF and ischemic events were the primary exposures following MI and their association with outcome SCA‐VA was assessed. Eight hundred and sixty‐seven patients (mean age was 63 ± 14.5 years; 69% male; 49.8% ST‐elevation myocardial infarction) who had their first type I MI during the study period were included. Majority of acute MI patients were revascularized using percutaneous coronary intervention and bypass surgery (628 [72.43%] and 87 [10.03%] respectively). During a mean follow‐up of 7.69 ± 4.17 years, HF, recurrent ischemic events and SCA‐VA occurred in 155 (17.9%), 245 (28.3%), and 40 (4.61%) patients respectively. Low ejection fraction (adjusted hazard ratio [HR] 0.95; 95% confidence interval [CI], 0.93‐0.98; P < .001), intercurrent HF (adjusted HR 3.11; 95% CI, 1.39‐6.95; P = .006) and recurrent ischemic events (adjusted HR 3.47; 95% CI, 1.68‐7.18; P < .001) were associated with subsequent SCA‐VA.ConclusionSCA‐VA occurred in a small proportion of patients after MI and is associated with intercurrent HF and recurrent ischemic events.
The impact of pulsed electromagnetic field therapy on blood pressure and circulating nitric oxide levels: a double blind, randomized study in subjects with metabolic syndrome
AbstractBackground and objectivesMacroreentrant atrial tachycardias often occur following atrial fibrillation ablation, most commonly due to nontransmural lesions in prior ablation lines. Perimitral atrial flutter is one such arrhythmia which requires ablation of the mitral isthmus. Our objectives were to review the literature regarding ablation of the mitral isthmus and to provide our approach for assessment of mitral isthmus block.MethodsWe review anatomical considerations, ablation strategies, and assessment of conduction block across the mitral isthmus, which is subject to several pitfalls. Activation sequence and spatial differential pacing techniques are discussed for assessment of both endocardial and epicardial bidirectional mitral isthmus block.ResultsTraditional methods for verifying mitral isthmus block include spatial differential pacing, activation mapping, and identification of double potentials. Up to 70% of cases require additional ablation in the coronary sinus (CS) to achieve transmural block. Interpretation of transmural block is subject to six pitfalls involving pacing output, differentiation of endocardial left atrial recordings from epicardial CS recordings, identification of a slowly conducting gap in the line, and catheter positioning during spatial differential pacing. Interpretation of unipolar electrograms can identify nontransmural lesions. We employ a combined epicardial and endocardial assessment of mitral isthmus block, which involves using a CS catheter for epicardial recording and a duodecapolar Halo catheter positioned around the mitral annulus for endocardial recording.ConclusionsThe assessment of transmural mitral isthmus block can be challenging. Placement of an endocardial mapping catheter around the mitral annulus can provide a precise assessment of conduction across the mitral isthmus.
Abstract PR10: Development of a comprehensive colorectal cancer risk prediction tool (CRiPT) incorporating known and unknown major genes and polygenes
Abstract Aim: We aimed to develop a comprehensive Colorectal cancer Risk Prediction Tool (CRiPT). To achieve this, it is necessary to incorporate germline mutations in the DNA mismatch repair genes and MUTYH to account for a proportion of the familial aggregation of colorectal cancer. Population prevalence of these mutations and the genetic and environmental causes of the remaining familial aggregation, however, are not known. Methods: We studied the families of 5,744 colorectal cancer cases (probands) recruited from population cancer registries in the USA, Canada and Australia, and screened probands for mutations in the mismatch repair genes MLH1, MSH2, MSH6, and PMS2, and MUTYH. We fitted modified segregation analysis models to the cancer history of first-degree relatives, conditional on the age at diagnosis of the proband, using the software MENDEL. We determined the genetic model that best explained the familial aggregation of colorectal cancer by estimating the prevalence of mutations in the known susceptibility genes, the prevalence of and hazard ratio for unmeasured high-risk gene mutations, and the variance of the unmeasured polygenic component, using a χ2 goodness-of-fit test. Results: The best fitting model was a mixed dominant model with the polygenic standard deviation varying by age. Under that model, we estimated 1 in 279 of the population carry mutations in the mismatch repair genes (MLH = 1 in 1946, MSH2 = 1 in 2841, MSH6 = 1 in 758, PMS2 = 1 in 714), 1 in 45 carry mutations in MUTYH, and 1 in 504 carry mutations in unknown major gene(s) which are associated with on average a 31-fold increased risk of colorectal cancer. The estimated variance of the polygenic component decreased from 1.8 for age <40 years to 0.7 for age ≥70 years (equivalent to a sibling relative risk of 5.1 and 1.3, respectively). There was good internal consistency in the best fitting model; i.e., predicted and observed numbers were close. Conclusion: CRiPT is a comprehensive prediction model that incorporates both known and unknown major genes and polygenes. CRiPT can provide the probabilities of having a mutation in a DNA mismatch repair gene or MUTYH as well as estimate future risk (e.g., 5-year risk) of developing colorectal cancer. This model is similar to the Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) that calculates for women the probabilities of carrying a BRCA1 or BRCA2 mutation and their future risk of developing breast and ovarian cancer based on their family history. Further work will include measured environmental factors and genetic variants to CRiPT, and it will be useful for genetic counselling and targeted colorectal cancer screening in clinical practices. This abstract is also being presented as Poster B04. Citation Format: Aung Ko Win, Mark A. Jenkins, James G. Dowty, Antonis C. Antoniou, Andrew Lee, Yingye Zheng, Noralane M. Lindor, Polly A. Newcomb, John L. Hopper, Robert J. MacInnis. Development of a comprehensive colorectal cancer risk prediction tool (CRiPT) incorporating known and unknown major genes and polygenes. [abstract]. In: Proceedings of the AACR Special Conference: Improving Cancer Risk Prediction for Prevention and Early Detection; Nov 16-19, 2016; Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(5 Suppl):Abstract nr PR10.
Abstract B04: Development of a comprehensive colorectal cancer risk prediction tool (CRiPT) incorporating known and unknown major genes and polygenes
Abstract This abstract is being presented as a short talk in the scientific program. A full abstract is printed in the Proffered Abstracts section (PR10) of the Conference Proceedings. Citation Format: Aung Ko Win, Mark A. Jenkins, James G. Dowty, Antonis C. Antoniou, Andrew Lee, Yingye Zheng, Noralane M. Lindor, Polly A. Newcomb, John L. Hopper, Robert J. MacInnis. Development of a comprehensive colorectal cancer risk prediction tool (CRiPT) incorporating known and unknown major genes and polygenes. [abstract]. In: Proceedings of the AACR Special Conference: Improving Cancer Risk Prediction for Prevention and Early Detection; Nov 16-19, 2016; Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(5 Suppl):Abstract nr B04.
Sex Differences in Nonalcoholic Fatty Liver Disease: State of the Art and Identification of Research Gaps
Despite tremendous research advancements in nonalcoholic fatty liver disease (NAFLD), our understanding of sex differences in NAFLD remains insufficient. This review summarizes the current knowledge on sex differences in NAFLD, identifies gaps, and discusses important considerations for future research. The prevalence and severity of NAFLD are higher in men than in women during the reproductive age. However, after menopause, NAFLD occurs at a higher rate in women, suggesting that estrogen is protective. Sex differences also exist for the major risk factors of NAFLD. In general, animal models of NAFLD recapitulate the sex differences observed in patients, with more severe steatosis and steatohepatitis, more proinflammatory/profibrotic cytokines, and a higher incidence of hepatic tumors in male than female subjects. Based on computer modeling, female and male livers are metabolically distinct with unique regulators modulating sex‐specific metabolic outcomes. Analysis of the literature reveals that most published clinical and epidemiological studies fail to examine sex differences appropriately. Considering the paucity of data on sex differences and the knowledge that regulators of pathways relevant to current therapeutic targets for NAFLD differ by sex, clinical trials should be designed to test drug efficacy and safety according to sex, age, reproductive stage (i.e., menopause), and synthetic hormone use. Conclusion: Sex differences do exist in the prevalence, risk factors, fibrosis, and clinical outcomes of NAFLD, suggesting that, while not yet incorporated, sex will probably be considered in future practice guidelines; adequate consideration of sex differences, sex hormones/menopausal status, age, and other reproductive information in clinical investigation and gene association studies of NAFLD are needed to fill current gaps and implement precision medicine for patients with NAFLD.
A Systematic Review of Noninvasive Electrocardiogram Monitoring Devices for the Evaluation of Suspected Cardiovascular Syncope
The aims of this study were (1) to identify research publications studying noninvasive electrocardiogram (ECG) monitoring devices, (2) to define and categorize current technology in noninvasive ECG recording, and (3) to discuss desirable noninvasive recording features for personalized syncope evaluation to guide technological advancement and future studies. We performed a systematic review of the literature that assessed noninvasive ECG-monitoring devices, regardless of the reason for monitoring. We performed an Internet search and corresponded with syncope experts and companies to help identify further eligible products. We extracted information about included studies and device features. We found 173 relevant papers. The main reasons for ECG monitoring were atrial fibrillation (n = 45), coronary artery disease (n = 10), syncope (n = 8), palpitations (n = 8), other cardiac diseases (n = 67), and technological aspects of monitoring (n = 35). We identified 198 devices: 5 hospital telemetry devices, 12 patches, 46 event recorders, 70 Holter monitors, 23 external loop recorders, 20 mobile cardiac outpatient telemetries, and 22 multifunctional devices. The features of each device were very heterogeneous. There are a large number of ECG-monitoring devices with different features available in the market. Our findings may help clinicians select the appropriate device for their patients. Since there are only a few published articles analyzing their usefulness in syncope patients, further research might improve their use in this clinical setting.
A randomized trial of three novel regimens for recurrent acute myeloid leukemia demonstrates the continuing challenge of treating this difficult disease
To improve the outcome of relapsed/refractory acute myeloid leukemia (AML), a randomized phase II trial of three novel regimens was conducted. Ninety patients were enrolled and were in first relapse or were refractory to induction/re‐induction chemotherapy. They were randomized to the following regimens: carboplatin‐topotecan (CT), each by continuous infusion for 5 days; alvocidib (formerly flavopiridol), cytarabine, and mitoxantrone (FLAM) in a timed sequential regimen; or sirolimus combined with mitoxantrone, etoposide, and cytarabine (S‐MEC). The primary objective was attainment of a complete remission (CR). A Simon two‐stage design was used for each of the three arms. The median age of the patients in the FLAM arm was older at 62 years compared with 55 years for the CT arm and the S‐MEC arm. The overall response was 14% in the CT arm (5/35, 90% CI 7%‐35%), 28% in the FLAM arm (10/36, 90% CI, 16%‐43%), and 16% in the S‐MEC arm (3/19, 90% CI, 4%‐36%). There were nine treatment‐related deaths, seven of which occurred in the FLAM arm with four of these in elderly patients. We conclude that the FLAM regimen had an encouraging response rate and should be considered for further clinical development but should be used with caution in elderly patients.
Risks of Colorectal Cancer and Cancer-Related Mortality in Familial Colorectal Cancer Type X and Lynch Syndrome Families
Abstract Background The risk of cancers is well characterized in Lynch syndrome (LS) families but has been less studied in familial colorectal cancer type X (FCCTX) families. Methods In this article, we compare the risk estimates of first and second colorectal cancers (CRCs) in 168 FCTTX and 780 LS families recruited through the Colon Cancer Family Registry as well as the risk of cancer-related deaths and disease-free survival (DFS) after a first CRC. Our methodology is based on a survival analysis approach, developed specifically to model the occurrence of successive cancers (ie, first and second CRCs) in the presence of competing risk events (ie, death from any causes). Results We found an excess risk of first and second CRC in individuals with LS compared to FCCTX family members. However, for an average age at first CRC of 60 years in FCCTX families and 50 years in LS families, the DFS rates were comparable in men but lower in women from FCCTX vs LS families, eg , 75.1% (95% confidence interval [CI] = 69.0% to 80.9%) vs 78.9% (95% CI = 76.3% to 81.3%) for the 10-year DFS. The 10-year risk of cancer-related death was higher in FCCTX families vs LS families, eg, 15.4% in men (95% CI = 10.9% to 19.8%) and 19.3% in women (95% CI = 13.6% to 24.7%) vs 8.9% (95% CI = 7.5% to 11.4%) and 8.7% (95% CI = 7.1% to 10.8%), respectively. Conclusions Individuals with CRCs arising in the context of FCCTX do not experience the same improved DFS and overall survival of those with LS, and that difference may be relevant in management decisions.
Physical activity and the risk of colorectal cancer in Lynch syndrome
Greater physical activity is associated with a decrease in risk of colorectal cancer for the general population; however, little is known about its relationship with colorectal cancer risk in people with Lynch syndrome, carriers of inherited pathogenic mutations in genes affecting DNA mismatch repair (MMR). We studied a cohort of 2,042 MMR gene mutations carriers (n = 807, diagnosed with colorectal cancer), from the Colon Cancer Family Registry. Self‐reported physical activity in three age‐periods (20–29, 30–49 and ≥50 years) was summarized as average metabolic equivalent of task hours per week (MET‐hr/week) during the age‐period of cancer diagnosis or censoring (near‐term exposure) and across all age‐periods preceding cancer diagnosis or censoring (long‐term exposure). Weighted Cox regression was used to estimate the hazard ratio (HR) and 95% confidence intervals (CI) for the association between physical activity and colorectal cancer risk. Near‐term physical activity was associated with a small reduction in the risk of colorectal cancer (HR ≥35 vs. <3.5 MET‐hr/week, 0.71; 95% CI, 0.53–0.96). The strength and direction of associations were similar for long‐term physical activity, although the associations were not nominally significant. Our results suggest that physical activity is inversely associated with the risk of colorectal cancer for people with Lynch syndrome; however, further confirmation is warranted. The potential modifying effect of physical activity on colorectal cancer risk in people with Lynch syndrome could be useful for risk prediction and support counseling advice for lifestyle modification to reduce cancer risk.