Radial Arteriovenous Fistula After a Left Heart Catheterization: Two Case Reports.

The distal transradial artery (TRA) approach has been increasing in popularity over recent years due to its favorable ergonomics and potential for fewer vascular complications. Other advantages include lower bleeding risk, early ambulation, lower procedural costs, and same-day discharge, resulting in additional cost savings. We discuss two cases of patients who underwent left heart catheterizations through the radial artery access site and afterwards experienced fistula formation. Our case series brings to light a rare occurrence of arteriovenous fistulas (AVFs) following cardiac catheterization via the transradial artery site, thus enhancing our knowledge of the risk associated with this access site. The pathophysiology of AV fistula remains the same regardless of transfemoral or transradial artery use. During the procedure, needle diversion into the venous tributary results in an unrecognized combined artery and vein puncture, which usually seals spontaneously. However, if the communication persists, an AV fistula may occur. The majority of patients who suffer from an iatrogenic AVF as a result of TRA do not develop clinical signs of hemodynamic significance. There are various therapeutic strategies, which include surgical repair, placement of a covered stent, ultrasound-guided compression of the AV fistula, and conservative management. Both of our patients were evaluated by vascular surgery; one of the patients found the constant pulsation and bruit burdensome and underwent surgical repair.

Ventricular fibrillation arrest due to Brugada syndrome in a coronavirus disease 2019 patient with negative procainamide challenge: a case report.

BACKGROUND: Pharmacologic challenge test is often used to diagnose Brugada syndrome (BrS) when spontaneous electrocardiograms (ECG) do not show type I Brugada pattern but reported sensitivity varies. The role of the exercise stress test in diagnosing Brugada syndrome is not well-established. CASE SUMMARY: A patient had a type I Brugada pattern ECG during the recovery phase of exercise stress test but had a negative procainamide challenge test. He had a loop recorder implanted and later survived a ventricular fibrillation (VF) arrest provoked by coronavirus disease 2019 (COVID-19). Electrocardiogram on arrival showed type 1 Brugada pattern. He was discharged after implantable cardioverter-defibrillator implantation. He later underwent genetic testing and was found to be heterozygous for c.844C>G (p.Arg282Gly) mutation in the SCN5A gene. DISCUSSION: Type 1 Brugada pattern ECG may be unmasked by ST-segment augmentation during recovery from exercise. Exercise stress test may play a role in the diagnosis of Brugada syndrome when suspicion for Brugada syndrome remains after a negative procainamide challenge test or if the patient has exercise-related symptoms. COVID-19 can unmask BrS and trigger a VF cardiac arrest.

Coronary artery disease in South Asian immigrants living in New York City: angiographic findings and risk factor burdens.

BACKGROUND: The prevalence of coronary artery disease (CAD) among South Asians (SAs) significantly exceeds that of Caucasians. South Asians also suffer from more premature, clinically aggressive and angiographically extensive (3-vessel) disease. The role of conventional CAD risk factors (CCRFs) remains controversial. OBJECTIVES: We sought to determine if the CCRF burdens of SA immigrants differed from Caucasians. We also sought to determine whether angiographic CAD was more extensive among SAs and whether SA ethnicity was an independent predictor of 3-vessel disease. METHODS: We reviewed the CCRFs and angiograms of 520 SAs and 219 Caucasians consecutively referred with stable angina pectoris or acute coronary syndrome. RESULTS: Three-vessel CAD was significantly more common among SAs than Caucasians (32.5% vs 22.4%; P = .006). Diabetes mellitus (DM), age and male sex independently predicted 3-vessel disease. South Asian ethnicity showed a trend toward predicting 3-vessel disease (P = .06). The frequency of DM (55% vs 31.1%; P < .001), hypertension (77.5% vs 68.5%; P = .01), obesity (63.1% vs 44.3%; P < .001) and dyslipidemia (75.6% vs 61.6%; P < .001) were significantly greater among SAs; however, smoking was significantly more common among Caucasians (44.3% vs 21.3%; P < .001). Compared to Caucasians, SAs were significantly younger at the time of presentation for coronary angiography (58.5 vs 61.1 yrs; P = .001). CONCLUSIONS: SAs referred for coronary angiography with stable angina and acute coronary syndromes are younger, have significantly higher rates of 3-vessel disease, as well as higher rates of DM, hypertension, obesity and dyslipidemia than Caucasians. Aggressive screening, prevention and treatment may be warranted in this population.

Coronary angiographic findings and conventional coronary artery disease risk factors of Indo-Guyanese immigrants with stable angina pectoris and acute coronary syndromes.

BACKGROUND: The prevalence of coronary artery disease (CAD) among migrant Indian populations exceeds that of Caucasians. Migrant Indians also suffer from more premature, clinically aggressive and angiographically extensive, (i.e., 3-vessel disease). It is not known whether the extent of angiographic CAD or the conventional CAD risk factors of Indo-Guyanese (IG) immigrants differs from that of Caucasians. METHODS: We reviewed the conventional CAD risk factors and angiographic findings of 198 IG and 191 Caucasians who were consecutively referred for cardiac catheterization with a diagnosis of stable angina pectoris or acute coronary syndrome. RESULTS: Three-vessel CAD was approximately 1.5 times more common among IG than Caucasians (34.8% vs. 24.0%; P = .02). Age (P = .01), male sex (P = .03) and diabetes mellitus (P = .05) were independently associated with an increased likelihood of 3-vessel CAD and there was a trend towards IG ethnicity predicting 3-vessel disease (P = .13). The frequency of diabetes mellitus (51.5% vs. 30.9%; P <.001), hypertension (82.3% vs. 67.0%; P < .001) and dyslipidemia (75.5% vs. 60.2%; P = .001) were significantly greater among IG, however, that of smoking was not. While IG were significantly leaner than Caucasians (27.7 kg/m2 vs. 30.0 kg/m2 ; P < .001), their mean body mass index fell within the ethnic-specific range for obesity. CONCLUSIONS: We conclude that IG immigrants presenting for coronary angiography have significantly higher rates of 3-vessel CAD as well as higher rates of diabetes mellitus, hypertension and dyslipidemia than Caucasians. Aggressive screening, prevention and treatment may be warranted in this cohort.

Atheroscerlotic heart disease in Bangladeshi immigrants: risk factors and angiographic findings.

BACKGROUND: The prevalence of coronary artery disease (CAD) among Bangladeshis greatly exceeds that of Caucasians. Bangladeshis also suffer from premature onset, clinically aggressive and angiographically extensive disease. The role of conventional CAD risk factors (CCRFs) has been questioned. We therefore sought to determine if the CCRFs of Bangladeshis differed from non-Bangladeshis. We also sought to determine whether CAD was more extensive in Bangladeshis and if Bangladeshi ethnicity was independently predictive of extensive i.e., 3-vessel CAD at angiography. METHODS: We reviewed the coronary angiograms and medical records of 75 Bangladeshis and 57 non-Bangladeshis presenting with myocardial infarction or angina pectoris. RESULTS: Bangladeshis were younger (56.1 vs. 62.4 years, p=.001), had a lower body-mass index (25.2 vs. 27.2 kg/m(2), p=.017) and were less likely to be current or recent smokers (40% vs. 58%, p=.041) than non-Bangladeshis. There were no statistically significant differences in the proportion of subjects in the 2 groups with respect to diabetes mellitus, dyslipidemia, hypertension or family history of CAD. Bangladeshis had twice the rate of 3-vessel CAD of non-Bangladeshis (53% vs. 26%, p=.002). Bangladeshi ethnicity was independently associated with >3X the likelihood of having 3-vessel CAD at angiography (p=.011). CONCLUSIONS: This study demonstrated that the CCRF burden of Bangladeshis with CAD is not excessive compared to that of non-Bangladeshis and is therefore unlikely to account for the excessive CAD risk found in this cohort. We also conclude that Bangladeshis have more angiographically extensive CAD than non-Bangladeshis and that Bangladeshi ethnicity is independently predictive of 3-vessel disease.

Prognostic implications of normal (<0.10 ng/ml) and borderline (0.10 to 1.49 ng/ml) troponin elevation levels in critically ill patients without acute coronary syndrome.

Borderline increase of troponin I (cTnI) is associated with higher rates of cardiovascular events compared with normal levels in the setting of acute coronary syndrome (ACS), but the significance of borderline cTnI levels in patients without chest pain may differ. The aim of this study was to determine the prognostic implications of intermediate serum cTnI levels in patients without ACS in the intensive care unit (ICU). This was a 12-month retrospective study of 240 patients without ACS in the ICU with normal (<0.1 ng/ml) or intermediate (0.1 to 1.49 ng/ml) cTnI levels. End points included in-hospital mortality, lengths of ICU and hospital stays, and rates of postdischarge readmission and mortality. Overall in-hospital mortality was 13%, with 5% in the normal cTnI group and 28% in the intermediate cTnI group. By multivariate analysis, intermediate cTnI was independently associated with in-hospital mortality (p = 0.004) and length of ICU stay (p = 0.028). The only other independent risk factor for inpatient mortality was a standardized ICU prognostic measurement (Simplified Acute Physiology Score II score). Intermediate cTnI had no prognostic implications regarding length of hospital stay, readmission rate, or postdischarge mortality at 6 months. In conclusion, an intermediate level of cTnI in patients without ACS in the ICU is an independent prognostic marker predicting in-hospital mortality and length of ICU stay. Patients with intermediate cTnI levels who survive to discharge have equivalent out-of-hospital courses for up to 6 months compared with patients with normal cTnI levels.

Limitation of the resting ankle-brachial index in symptomatic patients with peripheral arterial disease.

Peripheral arterial disease (PAD) has been demonstrated to be prevalent in the primary care setting. However, it has also been shown to be unrecognized and under-treated. Owing to the association with cardiovascular disease it has been recommended to screen high-risk patients for PAD in the primary care setting using the ankle-brachial index (ABI). ABI has been demonstrated to be highly sensitive and specific in diagnosing PAD in patients with significant stenosis. However, the utility in patients with less severe stenosis and calcified vessels is in question. The aims of this study were to determine the diagnostic utility of measuring the ABI at rest in patients referred to the vascular laboratory for evaluation of suspected PAD, and to assess the added value of pulse volume recordings and post-exercise studies in patients with a normal ABI. A computerized vascular diagnostic laboratory database was queried for symptomatic outpatients referred for measurement of segmental blood pressure, the ABI or pulse volume recordings by physicians not specialized in the evaluation and management of patients with peripheral vascular disease. Of 707 patients undergoing outpatient physiologic arterial evaluations between February 1, 2003 and July 31, 2004, 396 met these inclusion criteria. Data recorded included resting ABI, ABI following treadmill exercise test and the presence of abnormal pulse volume recordings. The study population (n = 396) consisted of equal numbers of men and women (mean age 69 years, range 19-100 years). Among 396 studies, resting ABI values were normal in 183 (46.2%) and abnormal in 159 (40.2%). Of the 138 patients who underwent exercise testing, 84 had normal ABI readings at rest. In the 84 patients who had a normal ABI at rest and underwent exercise testing, the ABI fell below 0.9 after exercise in 26 (31%). Arterial non-compressibility was detected in 54 (13.6%) patients, whose average age was 67 years. Thirteen (24%) of those with non-compressible vessels had abnormal pulse volume recording (PVR) results, compared to five with normal resting ABI who had abnormal PVR findings (2.7%). In conclusion, this study demonstrated that nearly half of patients referred to the outpatient vascular laboratory because of suspected arterial disease had a normal resting ABI. While it is recommended that the ABI be measured at rest in patients at risk of PAD in primary care practice, these findings suggest that patients with symptoms of PAD should be more completely evaluated in a vascular laboratory. Furthermore, when the ABI is normal at rest in patients with symptoms of intermittent claudication, exercise testing is recommended to enhance the sensitivity for detection of PAD.

Microvolt T-wave alternans for the risk stratification of ventricular tachyarrhythmic events: a meta-analysis.

OBJECTIVES: The objective of this study was to perform a meta-analysis of the predictive value of microvolt T-wave alternans (MTWA) testing for arrhythmic events in a wide variety of populations. BACKGROUND: Previous studies describing the use of MTWA as a predictor of ventricular tachyarrhythmic events have been limited by small sample sizes and disparate populations. METHODS: Prospective studies of the predictive value of exercise-induced MTWA published between January 1990 and December 2004 were retrieved. Data from each article were abstracted independently by two authors using a standardized protocol. Summary estimates of the predictive value of MTWA were made using a random-effects model. RESULTS: Data were accumulated from 19 studies (2,608 subjects) across a wide range of populations. Overall, the positive predictive value of MTWA for arrhythmic events was 19.3% at an average of 21 months' follow-up (95% confidence interval [CI] 17.7% to 21.0%), the negative predictive value was 97.2% (95% CI 96.5% to 97.9%), and the univariate relative risk of an arrhythmic event was 3.77 (95% CI 2.39 to 5.95). There was no difference in predictive value between ischemic and nonischemic heart failure subgroups. The positive predictive value varied depending on the population of patients studied (p < 0.0001). CONCLUSIONS: Microvolt T-wave alternans testing has significant value for the prediction of ventricular tachyarrhythmic events; however, there are significant limitations to its use. The predictive value of MTWA varies significantly depending on the population studied. Careful standardization is needed for what constitutes abnormal MTWA. The incremental prognostic value of MTWA when used with other methods of risk stratification is unclear.