Associations of combined polygenic risk score and glycemic status with atrial fibrillation, coronary artery disease and ischemic stroke.

BACKGROUND: It is unknown whether high hemoglobin A1c (HbA1c) is associated with increases in the risk of cardiovascular disease among individuals with elevated genetic susceptibility. We aimed to investigate the association between HbA1c and atrial fibrillation (AF), coronary artery disease (CAD), and ischemic stroke according to the polygenic risk score (PRS). METHODS: The UK Biobank cohort included 502,442 participants aged 40-70 years who were recruited from 22 assessment centers across the United Kingdom from 2006 to 2010. This study included 305,605 unrelated individuals with available PRS and assessed new-onset AF, CAD, and ischemic stroke. The participants were divided into tertiles based on the validated PRS for each outcome. Within each PRS tertiles, the risks of incident events associated with HbA1c levels were investigated and compared with HbA1c < 5.7% and low PRS. Data were analyzed from November 2022 to May 2023. RESULTS: Of 305,605 individuals, 161,605 (52.9%) were female, and the mean (SD) age was 56.6 (8.1) years. During a median follow-up of 11.9 (interquartile range 11.1-12.6) years, the incidences of AF, CAD, and ischemic stroke were 4.6, 2.9 and 1.1 per 100 person-years, respectively. Compared to individuals with HbA1c < 5.7% and low PRS, individuals with HbA1c ≥ 6.5% and high PRS had a 2.67-times higher risk for AF (hazard ratio [HR], 2.67; 95% confidence interval (CI), 2.43-2.94), 5.71-times higher risk for CAD (HR, 5.71; 95% CI, 5.14-6.33) and 2.94-times higher risk for ischemic stroke (HR, 2.94; 95% CI, 2.47-3.50). In the restricted cubic spline models, while a U-shaped trend was observed between HbA1c and the risk of AF, dose-dependent increases were observed between HbA1c and the risk of CAD and ischemic stroke regardless PRS tertile. CONCLUSIONS: Our results suggest that the nature of the dose-dependent relationship between HbA1c levels and cardiovascular disease in individuals with different PRS is outcome-specific. This adds to the evidence that PRS may play a role together with glycemic status in the development of cardiovascular disease.

Risk of dementia in stroke-free patients diagnosed with atrial fibrillation: data from a population-based cohort.

AIMS: Atrial fibrillation (AF) is generally regarded as a risk factor for dementia, though longitudinal studies assessing the association between AF and dementia have shown inconsistent results. This study aimed to determine the effect of AF on the risk of developing dementia using a longitudinal, community-based, and stroke-free elderly cohort. METHODS AND RESULTS: The association of incident AF with the development of incident dementia was assessed from 2005 to 2012 in 262 611 dementia- and stroke-free participants aged ≥60 years in the Korea National Health Insurance Service-Senior cohort. Incident AF was observed in 10 435 participants over an observational period of 1 629 903 person-years (0.64%/year). During the observational period, the incidence of dementia was 4.1 and 2.7 per 100 person-years in the incident AF and propensity score-matched AF-free groups, respectively. After adjustment, the risk of dementia was significantly increased by incident AF with a hazard ratio (HR) of 1.52 [95% confidence interval (CI) 1.43-1.63], even after censoring for stroke (1.27, 95% CI 1.18-1.37). Incident AF increased the risk of both Alzheimer (HR 1.31, 95% CI 1.20-1.43) and vascular dementia (HR 2.11, 95% CI 1.85-2.41). Among patients with incident AF, oral anticoagulant use was associated with a preventive effect on dementia development (HR 0.61, 95% CI 0.54-0.68), and an increasing CHA2DS2-VASc score was associated with a higher risk of dementia. CONCLUSION: Incident AF was associated with an increased risk of dementia, independent of clinical stroke in an elderly population. Oral anticoagulant use was linked with a decreased incidence of dementia.

Associations of high-normal blood pressure and impaired fasting glucose with atrial fibrillation.

OBJECTIVE: To investigate the association of high-normal blood pressure (BP) and impaired fasting glucose (IFG) with the risk of atrial fibrillation (AF) in two cohorts. METHODS: The Korean National Health Insurance Service-Health Screening (K-NHIS-HealS, 2002-2003, follow-up until 2013) Study and the UK Biobank (2007-2010, follow-up until 2021) were evaluated. We used Cox proportional hazards regression models to evaluate the associations of high-normal BP and IFG with incident AF. RESULTS: In the K-NHIS-HealS and the UK Biobank, 2346 and 5314 incident AF events were recorded during the mean follow-up of 7.4 and 11.8 years. The adjusted HRs (95% CIs) for AF in the Korean and UK cohorts were 1.11 (1.02 to 1.21) and 1.07 (1.01 to 1.13) in individuals with high-normal BP; and 1.14 (1.04 to 1.25) and 1.10 (1.01 to 1.20) in individuals with IFG, respectively. The AF risk showed a dose-response relationship with BP and fasting blood glucose level. The risk of incident AF was increased by the combination of high-normal BP and IFG. CONCLUSIONS: In healthy individuals, high-normal BP and IFG were important risk factors for AF. When high-normal BP and IFG were combined, the risk of new-onset AF was significantly increased. These findings may suggest that lifestyle interventions for high-normal BP and IFG should be considered to reduce the risk of AF.

Association of Light-Intensity Physical Activity With Mortality in the Older Population: A Nationwide Cohort Study.

Background: There is a paucity of information about mortality related to light-intensity physical activity (LPA) in the older population. We examine the associations between physical activity and mortality, focusing on the effect of light-intensity physical activity and the dose-response relationship between physical activity and mortality. Methods: We analyzed a total of 58,537 participants aged ≥ 65 years (mean age, 73.9 ± 5.8 years; male, 36.0%) in the Korean National Health Insurance Service database between 2009 and 2012. The Date of the end of follow-up was December 31, 2013. Individuals were divided into four categories according to physical activity intensity: totally sedentary (43.3%), LPA only (35.8%), LPA and moderate- to vigorous-intensity physical activity (MVPA) (16.3%), MVPA only (4.5%). Physical activity was quantified using standardized self-reported questionnaires which composed of the duration and frequency of physical activity. Results: During a mean follow-up of 39.6 ± 14.0 months, 5,651 (9.7%) deaths occurred. Compared with totally sedentary individuals, those in the LPA only, LPA and MVPA, and MVPA only groups showed 26% [hazard ratio (HR) 0.74, 95% confidence interval (CI) 0.68-0.82], 27% (HR 0.73, 95% CI 0.63-0.84), and 34% (HR 0.66, 95% CI 0.54-0.79) lower all-cause mortality risk, showing an inverse relationship between physical activity intensity and mortality risk. In contrast, the LPA only, LPA and MVPA, and MVPA only groups represented a stronger inverse association with CV mortality (LPA: HR 0.76, 95% CI 0.62-0.92; LPA with MVPA: HR 0.74, 95% CI 0.55-0.999; MVPA, HR 0.57, 95% CI 0.37-0.87). Among participants performing LPA alone, participants performing less than the recommended dose of physical activity had lower all-cause mortality than those with sedentary activity (1-249 MET-min/week: HR 0.74, 95% CI 0.67-0.82, 250-499 MET-min/week: HR 0.65, 95% CI 0.59-0.72). Conclusion: Physical activity, even low doses of LPA, was associated with reduced mortality risk in the elderly population. This study may motivate sedentary individuals to engage in any physical activity for mortality benefits.

Drug Utilization Pattern of Oral Anticoagulants in Patients with Atrial Fibrillation: A Nationwide Population-Based Study in Korea.

INTRODUCTION: Treatment persistence for anticoagulant therapy is important in preventing thromboembolism in nonvalvular atrial fibrillation (NVAF) patients. Understanding drug utilization pattern and treatment changes in oral anticoagulant (OAC) users may facilite better NVAF management. Thus, our study aimed to examine OAC treatment patterns preceding events leading to switch or discontinuation and medication adherence in Korean NVAF patients. METHODS: We conducted a drug utilization study on all Korean patients with atrial fibrillation (AF) newly prescribed OACs between July 2015 and November 2016 using the national claims data. We assessed treatment changes such as switching and discontinuation from index OAC and relevant events preceding the change and examined patient characteristics as predictors of changes that occurred among OAC users. Medication adherence was compared among OAC users by calculating the medication possession ratio (MPR). RESULTS: A total of 48,389 NVAF patients were identified who initiated OACs within the study period. Most initiated nonvitamin K antagonist oral anticoagulants (NOACs) (22% apixaban, 24% dabigatran, 37% rivaroxaban), and 18% initiated warfarin. The frequency of switch to another OAC was 8.8% for apixaban, 16.1% for dabigatran, 6.6% for rivaroxaban, and 19.1% for warfarin. The frequency of discontinuation was lower for apixaban (22.9%), dabigatran (26.3%), and rivaroxaban (25.7%) than warfarin (31.6%). Compared to warfarin, NOAC users were less likely to switch treatment. Thromboembolic event was the most common clinical event preceding switch from warfarin to NOAC and from NOAC to warfarin. Discontinuation of OAC was often preceded by a bleeding event. Patients who initiated apixaban showed significantly higher mean MPR compared to those on dabigatran and warfarin. CONCLUSION: In real-world practice in Korea, we have observed treatment change to be common in OAC users. Our results indicate better medication adherence with NOACs than with warfarin. (ClinicalTrials.gov registration number NCT03572972).

Anticoagulants are drugs that thin blood with the purpose of preventing thromboembolic disease (e.g., stroke), which is a disease occurring when a blood clot forms or blocks vessel. Maintaining treatment for anticoagulation is important to prevent stroke in atrial fibrillation (AF) patients. To understand current drug usage pattern and treatment changes related to oral anticoagulants (OAC) we examined OAC treatment patterns and preceding events that led to drug switch or stop and medication maintenance by Korean AF patients.The study was conducted by utilizing the Korean national claims data from July 2015 to November 2016. All AF patients who newly started taking OAC were included in the analysis. In total, 48,389 patients were identified with most (83%) taking nonvitamin K antagonist oral anticoagulants (NOAC), which are newer generation blood thinners, including apixaban, dabigatran, and rivaroxaban, and 18% taking warfarin, the conventional blood thinner. Compared to warfarin, NOAC users were less likely to switch to other treatment. NOAC users discontinued the treatment less frequently than warfarin users. Thromboembolic events commonly preceded switch between OACs. Patients who stopped taking OACs were often confronted with a bleeding event before stopping treatment. Apixaban takers showed higher treatment persistence compared to dabigatran or warfarin users. In this study, we determined that treatment change is common in OAC-using patients. The results suggest that NOAC users may better adhere to treatment than warfarin users.

Comorbidities and Antithrombotic Treatment Pattern in Patients With Atrial Fibrillation.

Objective: Non-vitamin K antagonist oral anticoagulants (NOACs) are proven alternatives to warfarin for preventing stroke in patients with non-valvular atrial fibrillation. We aimed to examine the treatment patterns and patient factors associated with the use of antiplatelet agents, warfarin, and NOACs in clinical practice. Methods: We conducted a retrospective cohort study using the Korean Health Insurance Review & Assessment Service database. Patients receiving antithrombotics were identified before and after the introduction of NOACs (from August 1, 2013 to December 30, 2014 and July 1, 2015 to November 30, 2016, respectively). Patients were included if they were aged ≥18 years, had an atrial fibrillation diagnosis, and had a CHA2DS2-VASc score ≥2. Treatment pattern was assessed by classifying patients into NOAC, warfarin, or antiplatelet users based on the first date of antithrombotic prescription. Clinical factors associated with the type of antithrombotics chosen were examined using logistic regression analyses. Results: We identified 129,465 and 196,243 patients before and after the introduction of NOACs, respectively. The proportion of antiplatelet users was 60.7 and 53.0% before and after the introduction of NOACs, respectively. The proportion of warfarin users was higher in patients with low HAS-BLED score, high CHA2DS2-VASc score, or stroke before the NOAC era. A similar trend was observed for NOAC and warfarin users after the introduction of NOAC. Compared with antiplatelets, warfarin and NOAC uses were significantly associated with CHA2DS2-VASc score and stroke, whereas presence of myocardial infarction (MI) and peripheral arterial disease were significantly associated with antiplatelets prescription. For comparisons between NOAC and warfarin, HAS-BLED and CHA2DS2-VASc scores showed significant associations with NOAC use, whereas comorbidities including MI were significantly associated with warfarin use. Conclusions: The treatment pattern of antithrombotics did not change with the introduction of NOACs. However, comorbidities served as an important factor in choosing treatment regardless of NOAC entry.

Machine learning models of clinically relevant biomarkers for the prediction of stable obstructive coronary artery disease.

Background: In patients with suspected obstructive coronary artery disease (CAD), evaluation using a pre-test probability model is the key element for diagnosis; however, its accuracy is controversial. This study aimed to develop machine learning (ML) models using clinically relevant biomarkers to predict the presence of stable obstructive CAD and to compare ML models with an established pre-test probability of CAD models. Methods: Eight machine learning models for prediction of obstructive CAD were trained on a cohort of 1,312 patients [randomly split into the training (80%) and internal validation sets (20%)]. Twelve clinical and blood biomarker features assessed on admission were used to inform the models. We compared the best-performing ML model and established the pre-test probability of CAD (updated Diamond-Forrester and CAD consortium) models. Results: The CatBoost algorithm model showed the best performance (area under the receiver operating characteristics, AUROC, 0.796, and 95% confidence interval, CI, 0.740-0.853; Matthews correlation coefficient, MCC, 0.448) compared to the seven other algorithms. The CatBoost algorithm model improved risk prediction compared with the CAD consortium clinical model (AUROC 0.727; 95% CI 0.664-0.789; MCC 0.313). The accuracy of the ML model was 74.6%. Age, sex, hypertension, high-sensitivity cardiac troponin T, hemoglobin A1c, triglyceride, and high-density lipoprotein cholesterol levels contributed most to obstructive CAD prediction. Conclusion: The ML models using clinically relevant biomarkers provided high accuracy for stable obstructive CAD prediction. In real-world practice, employing such an approach could improve discrimination of patients with suspected obstructive CAD and help select appropriate non-invasive testing for ischemia.

Treatment Pattern of Antithrombotic Therapy over Time after Percutaneous Coronary Intervention in Patients with Atrial Fibrillation in Real-World Practice in Korea.

We examined antithrombotic treatment patterns with clinical characteristics and therapy changes over time in patients with atrial fibrillation (AF) after percutaneous coronary intervention (PCI). Using the Health Insurance Review and Assessment service claims database (01JAN2007-30NOV2016) in Korea, we included adult patients with AF and PCI: (1) who underwent PCI with stenting between 01JAN2008 and 30NOV2016; (2) with ≥1 claim for AF (ICD code: I48) (3) with antithrombotics 1 day prior to or at the date of PCI; and (4) with CHADS2-VASc of ≥2. In this study, 7749 patients with AF who underwent PCI, triple therapy, dual therapy, dual antiplatelet therapy (DAPT), and single antiplatelet therapy were prescribed to 24.6%, 3.4%, 60.8%, and 11.0%, respectively. In the triple therapy group, 23.1% persisted with triple therapy for 12 months, whereas the remaining patients switched to a different therapy. In the entire cohort and several subgroups, the median treatment duration of triple therapy was 55-87 days. DAPT use for 12 months was the most common treatment pattern (62.6%) in the DAPT group (median treatment duration, 324-345 days). A significant discrepancy exists between the current guidelines and real-world practice regarding antithrombotic treatment with PCI for patients with AF. Appropriate use of anticoagulants should be emphasized.

Effectiveness and safety of non-vitamin K antagonist oral anticoagulants in patients with non-valvular atrial fibrillation: A nationwide, population-based study in Korea.

BACKGROUND: To compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) between non-vitamin K antagonist oral anticoagulants (NOACs) in patients with atrial fibrillation (AF), this retrospective study was conducted using the Korean Health Insurance Review & Assessment Service (HIRA) claims database. METHODS: Patients with AF who initiated NOACs (apixaban, dabigatran, and rivaroxaban) from July 1, 2015 to November 30, 2016 were included. We applied inverse probability of treatment weighting (IPTW) method using propensity score to make weighted populations having similar characteristics between groups. Hazard ratio (HR) of S/SE and MB were estimated by Cox proportional hazard model. RESULTS: Of the 39 783 patients with AF, 10 564; 11 418; and 17 801 used apixaban, dabigatran, and rivaroxaban, respectively. The mean CHA2DS2-VASc and HAS-BLED scores were 4.59 ~ 4.69 and 3.58 ~ 3.62, respectively, among all patients after applying IPTW. For S/SE, there were no significant differences between NOACs (HR [95% confidence interval (CI)]): apixaban vs dabigatran (0.99 [0.87-1.13]), apixaban vs rivaroxaban (0.95 [0.84-1.07]), and dabigatran vs rivaroxaban (0.96 [0.85-1.08]). For MB (HR [95% CI]), both apixaban (0.77 [0.68-0.86]) and dabigatran (0.88 [0.79-0.98]) had a significantly lower risk compared with rivaroxaban. Apixaban also had a significantly lower risk of MB compared with dabigatran (0.87 [0.76-0.99]). CONCLUSIONS: In real-world practice among Korean AF patients with relatively high risk of stroke and bleeding, there were no significant differences in the risk of S/SE between all NOAC comparisons. Apixaban was associated with lower risk of MB than dabigatran and rivaroxaban.

Association of proteinuria and incident atrial fibrillation in patients with diabetes mellitus: a population-based senior cohort study.

Diabetes mellitus (DM) is considered an independent risk factor for atrial fibrillation (AF). The excess risk in relation to the presence of proteinuria has not been well elucidated. Our aim was to determine the association between the incidence of AF and proteinuria in diabetic population. A total of 240,499 individuals aged ≥ 60 years from the Korea National Health Insurance Service-Senior cohort from 2004 to 2014 were included. 4.2% of individuals with DM and 3.7% of controls were diagnosed with AF during a median follow-up period of 7.2 years. Amongst controls (participants without proteinuria and DM), DM only, proteinuria only, and DM with proteinuria groups, the crude incidences of AF were 0.58, 0.70, 0.96, 1.24 per 100 person-years respectively. Compared with controls, the weighted risk of AF was increased by 11% (hazard ratio = 1.11, 95% confidence interval = 1.02-1.20, P = .001), 48% (hazard ratio = 1.48, 95% confidence interval = 1.30-1.69, P < .001), and 66% (hazard ratio = 1.66, 95% confidence interval = 1.26-2.18, P < .001) in the DM only, proteinuria only, and DM with proteinuria groups, respectively (P for trend < .001). Degree of proteinuria in diabetic patients was associated with a significantly higher rate of incident AF in dose dependent manner. Thus, assessing proteinuria by a simple urine dipstick test could provide a useful adjunct to risk assessment for AF in elderly population with DM.

Impact of Reduced-Dose Nonvitamin K Antagonist Oral Anticoagulants on Outcomes Compared to Warfarin in Korean Patients with Atrial Fibrillation: A Nationwide Population-Based Study.

Reduced-dose nonvitamin K antagonist oral anticoagulants (NOACs) are commonly prescribed to Asian patients with nonvalvular atrial fibrillation (NVAF). We aimed to compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) between patients treated with reduced-dose NOACs and those treated with warfarin, using the claims database in Korea. Patients with NVAF newly initiated on oral anticoagulants (OACs; apixaban, dabigatran, rivaroxaban, and warfarin) between 1 July 2015 and 30 November 2016 were included. Among all patients with NVAF treated with OACs, 5249, 6033, 7602, and 8648 patients were treated with reduced-dose apixaban, dabigatran, rivaroxaban, and warfarin, respectively. Patients treated with reduced-dose NOACs were older and had higher CHA2DS2-VASc and HAS-BLED scores than those treated with warfarin. Compared to warfarin, all reduced-dose NOACs showed significantly lower risk of S/SE (hazard ratios (95% confidence interval), 0.63 (0.52-0.75) for apixaban; 0.51 (0.42-0.61) for dabigatran; and 0.67 (0.57-0.79) for rivaroxaban) and MB (0.54 (0.45-0.65) for apixaban; 0.58 (0.49-0.69) for dabigatran; 0.73 (0.63-0.85) for rivaroxaban). In the real-world practice among Asians with NVAF, all reduced-dose NOACs were associated with a significantly lower risk of S/SE and MB compared to those of warfarin.

The risk of stroke/systemic embolism and major bleeding in Asian patients with non-valvular atrial fibrillation treated with non-vitamin K oral anticoagulants compared to warfarin: Results from a real-world data analysis.

BACKGROUND: Although randomized trials provide a high level of evidence regarding the efficacy of non-vitamin K oral anticoagulants (NOACs), the results of such trials may differ from those observed in day-to-day clinical practice. AIMS: To compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) between NOAC and warfarin in clinical practice. METHODS: Patients with non-valvular atrial fibrillation (NVAF) who started warfarin/NOACs between January 2015 and November 2016 were retrospectively identified from Korea's nationwide health insurance claims database. Using inpatient diagnosis and imaging records, the Cox models with inverse probability of treatment weighting using propensity scores were used to estimate hazard ratios (HRs) for NOACs relative to warfarin. RESULTS: Of the 48,389 patients, 10,548, 11,414, 17,779 and 8,648 were administered apixaban, dabigatran, rivaroxaban and warfarin, respectively. Many patients had suffered prior strokes (36.7%, 37.7%, 31.4%, and 32.2% in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively), exhibited high CHA2DS2-VASc (4.8, 4.6, 4.6, and 4.1 in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively) and HAS-BLED (3.7, 3.6, 3.6, and 3.3 in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively) scores, had received antiplatelet therapy (75.4%, 75.7%, 76.8%, and 70.1% in apixaban, dabigatran, rivaroxaban, and warfarin group, respectively), or were administered reduced doses of NOACs (49.8%, 52.9%, and 42.8% in apixaban, dabigatran, and rivaroxaban group, respectively). Apixaban, dabigatran and rivaroxaban showed a significantly lower S/SE risk [HR, 95% confidence intervals (CI): 0.62, 0.54-0.71; 0.60, 0.53-0.69; and 0.71, 0.56-0.88, respectively] than warfarin. Apixaban and dabigatran (HR, 95% CI: 0.58, 0.51-0.66 and 0.75, 0.60-0.95, respectively), but not rivaroxaban (HR, 95% CI: 0.84, 0.69-1.04), showed a significantly lower MB risk than warfarin. CONCLUSIONS: Among Asian patients who were associated with higher bleeding risk, low adherence, and receiving reduced NOAC dose than that provided in randomised controlled trials, all NOACs were associated with a significantly lower S/SE risk and apixaban and dabigatran with a significantly lower MB risk than warfarin.

Spontaneous Transition of Double Tachycardias with Atrial Fusion in a Patient with Wolff-Parkinson-White Syndrome.

Among patients with Wolff-Parkinson-White syndrome, atrioventricular reciprocating tachycardia (AVRT) and atrioventricular nodal reentrant tachycardia (AVNRT) can coexist in a single patient. Direct transition of both tachycardias is rare; however, it can occur after premature atrial or ventricular activity if the cycle lengths of the two tachycardias are similar. Furthermore, persistent atrial activation by an accessory pathway (AP) located outside of the AV node during ongoing AVNRT is also rare. This article describes a case of uncommon atrial activation by an AP during AVNRT and gradual transition of the two supraventricular tachycardias without any preceding atrial or ventricular activity in a patient with preexcitation syndrome.

Determinants of maximal right ventricular function: role of septal shift.

BACKGROUND: Right heart failure can occur after orthotopic heart transplantation and can complicate implantation of left ventricular assist devices. The functional codeterminants of right ventricular function are not fully understood. We investigated the effects of left ventricular preload and afterload, systemic pressure, and the contribution of the interventricular septum to right ventricular function. METHODS AND RESULTS: In vivo studies were conducted in 12 dogs by using a highly defined, isovolumic right heart preparation. At any given arterial pressure, maximal right ventricular developed pressure was not influenced by left heart output; however, right ventricular volumes at which peak right ventricular developed pressure occurred differed significantly between the volume-loaded versus the unloaded left ventricle (P <.05). A correlation was found between peak right ventricular developed pressure and mean arterial pressure. The shift of the interventricular septum toward the left ventricle is delayed under the influence of left ventricular volume load, but the maximal interventricular septal deformation does not differ at maximal right ventricular developed pressure. There was a substantial and significant decrease in peak right ventricular developed pressure when the interventricular septum was inactivated (P <.05). CONCLUSIONS: Right ventricular function has multiple determinants, including the right ventricular free wall, the left ventricle, and the interventricular septum. Changes in right ventricular performance caused by alterations in left ventricular volume load and mean arterial pressure are mediated partially through the interventricular septum, as well as through perfusion of the right ventricular free wall; inactivation of the interventricular septum leads to a significant decrease in right ventricular function. Maintaining left ventricular developed pressure and hence the contribution of the interventricular septum to right ventricular function may be important in the management of right ventricular failure.

Tricuspid Regurgitation and Right Heart Dimensions at Early and Late Follow-Up After Orthotopic Cardiac Transplantation.

Tricuspid regurgitation is common immediately after cardiac transplantation, but its course over long-term follow-up is not known. This study was performed to determine the prevalence of valvular regurgitation and to evaluate if pulmonary hypertension or right ventricular enlargement were associated with the severity of tricuspid regurgitation at early and late follow-up after cardiac transplantation. Fifty-five patients had hemodynamic and echocardiographic studies performed at 1 week and 2.4 +/- 1.3 years after cardiac transplantation. Right ventricular dimensions were measured and related to the severity of tricuspid regurgitation as assessed by Doppler color flow. There was a fall in right heart filling pressures with decreases in the systolic pulmonary artery pressure (31 mmHg +/- 7 mmHg vs 27 mmHg +/- 7 mmHg, P = 0.0001) and right atrial pressure (8 +/- 5 mmHg vs 6 +/- 4 mmHg, P < 0.01). Sixty-three percent of patients had mild or higher grade tricuspid regurgitation initially and 71% at follow-up (P = NS). The major determinant of tricuspid regurgitation severity at late follow-up was the presence of flail tricuspid leaflets (P < 0.0001). There was an association between the change in grade of tricuspid regurgitation and the change in right ventricular diastolic area (P = 0.002) and the change in tricuspid annulus diameter (P < 0.0001). The prevalence of tricuspid regurgitation remains high at late follow-up after cardiac transplantation and neither pulmonary hypertension nor right ventricular dilatation are prerequisites for tricuspid regurgitation, which can persist in their absence. Flail tricuspid leaflets are the most important predictors of the severity of tricuspid regurgitation following cardiac transplantation.

Intermittent, non cyclic severe mechanical aortic valve regurgitation.

Mechanical aortic prosthesis dysfunction can result from thrombosis or pannus formation. We describe an unusual case of intermittent, non cyclic mechanical aortic prosthesis dysfunction due to pannus formation with thrombus in the absence of systolic restriction of disk excursion, that presented with intermittent severe aortic regurgitation.

Management of a remnant electrode in a patient with cardioverter-defibrillator infection after refusal of intravascular electrode removal.

Treatments of choice for cardiac implantable electronic device (CIED) infections are the removal of the entire CIED system, control of infection, and new device implantation. Occasionally, a complete CIED removal can not be performed for several reasons, such as very old age, severe comobidity, limited life expectancy, or refusal by a patient. We encountered a male patient who developed traumatic CIED infection five years after cardioverter-defibrillator implantation. An intravenous electrode could not be removed by a simple transvenous extraction procedure, and he refused surgical removal of the remnant electrode. After control of local infection, the tips of the electrode were separated and buried between muscles, and the wound was closed with a local flap. CIED infection did not recur for 12 months even without relying on long-term antimicrobial treatment.

Early detection of asymptomatic coronary artery disease in patients with type 2 diabetes mellitus.

BACKGROUND/AIMS: In type 2 diabetic patients, coronary artery disease (CAD) is usually detected at an advanced stage due to a lack of symptoms. The aim of this study was to define which clinical parameters or non-invasive tests predict CAD in asymptomatic type 2 diabetic patients. METHODS: One hundred fourteen asymptomatic type 2 diabetic patients were divided into two groups based on the number of cardiovascular disease (CVD) risk factors (group A>or=2, group Bor=10 years (OR=3.28; 95% CI, 1.29-8.84) were independent CAD risk factors in asymptomatic patients. CONCLUSIONS: We recommend a routine screening for CAD in type 2 diabetic patients who have a longer (>or=10 years) diabetic duration or a family history of CAD, even if they are asymptomatic for CAD.