Fragmented QRS, a strong predictor of mortality and major arrhythmic events in patients with nonischemic cardiomyopathy: A systematic review and meta-analysis.

Background and Aims: Fragmented QRS (fQRS), which is associated with rhythm disturbances, can predispose the heart to fatal ventricular arrhythmias. Recently, accumulating studies indicates that fQRS is associated with poor prognosis in various types of cardiomyopathies. Therefore, we assessed the association between fQRS with all-cause mortality and major arrhythmic events (MAEs) in patients with nonischemic cardiomyopathy, in this systematic review and meta-analysis study. Methods: We performed a comprehensive search in databases of PubMed/Medline, EMBASE, and Web of Science from the beginning to December 31, 2022. Published observational studies (cohorts, case-control, or analytical cross-sectional studies) were included that report the prognostic value of fQRS in patients with different types of nonischemic cardiomyopathies for MAEs (sudden cardiac death, sudden cardiac arrest, sustained ventricular tachycardia [VT], ventricular fibrillation [VF], and appropriate shock) and all-cause mortality. We pooled risk ratios (RRs) through raw data and adjusted hazard ratios (aHRs) using "Comprehensive Meta-Analysis" software, Version 2.0. Results: Nineteen cohort and three analytical cross-sectional studies were included in this meta-analysis involving a total of 4318 subjects with nonischemic cardiomyopathy (1279 with fQRS and 3039 without fQRS). FQRS was significantly associated with an increased risk of all-cause mortality in patients with nonischemic cardiomyopathy (pooled RR: 1.920; 95% confidence interval [CI]: 1.388-2.656, p < 0.0001/pooled HR: 1.729; 95% CI: 1.327-2.251, p < 0.0001). Also, the risk of developing MAEs in the presence of fQRS was significantly increased (pooled RR: 2.041; 95% CI: 1.644-2.533, p < 0.0001/pooled HR: 3.626; 95% CI: 2.119-6.204, p < 0.0001). In the subgroup analysis, the strongest association between fQRS presence and increased MAEs was observed in patients with hypertrophic cardiomyopathy (HCM) (pooled RR: 3.44; 95% CI: 2.07-5.71, p < 0.0001/pooled HR: 3.21; 95% CI: 2.04-5.06, p < 0.0001). Conclusion: Fragmented QRS could be a prognostic marker for all-cause mortality and MAEs in patients with various types of nonischemic cardiomyopathies, particularly HCM.

Predictors of pacemaker requirement in patients with implantable loop recorder and unexplained syncope: A systematic review and meta-analysis.

Identifying the underlying cause of unexplained syncope is crucial for appropriate management of recurrent syncopal episodes. Implantable loop recorders (ILRs) have emerged as valuable diagnostic tools for monitoring patients with unexplained syncope. However, the predictors of pacemaker requirement in patients with ILR and unexplained syncope remain unclear. In this study, we shed light on these prognostic factors. PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane CENTRAL were systematically searched until May 04, 2023. Studies that evaluated the predictors of pacemaker requirement in patients with implantable loop recorder and unexplained syncope were included. The "Quality In Prognosis Studies" appraisal tool was used for quality assessment. The pooled odds ratio (OR) with 95% confidence intervals (CIs) was calculated. The publication bias was evaluated using Egger's and Begg's tests. Ten studies (n = 4200) were included. Right bundle branch block (OR: 3.264; 95% CI: 1.907-5.588, p < .0001) and bifascicular block (OR: 2.969; 95% CI: 1.859-4.742, p < .0001) were the strongest predictors for pacemaker implantation. Pacemaker requirement was more than two times in patients with atrial fibrillation, sinus bradycardia and first degree AV block. Valvular heart disease, diabetes mellitus, and hypertension were also significantly more in patients with pacemaker implantation. Age (standardized mean difference [SMD]: 0.560; 95% CI: 0.410/0.710, p < .0001) and PR interval (SMD: 0.351; 95% CI: 0.150/0.553, p = .001) were significantly higher in patients with pacemaker requirement. Heart conduction disorders, atrial arrhythmias and underlying medical conditions are main predictors of pacemaker device implantation following loop recorder installation in unexplained syncopal patients.

Associations between short-term exposure to fine particulate matter and acute myocardial infarction: A case-crossover study.

BACKGROUND: Previous studies evaluated the impact of particle matters (PM) on the risk of acute myocardial infarction (AMI) based on local registries. HYPOTHESIS: This study aimed to evaluate possible short term effect of air pollutants on occurrence of AMI based on a specific case report sheet that was designed for this purpose. METHODS: AMI was documented among 982 patients who referred to the emergency departments in Tehran, Iran, between July 2017 to March 2019. For each patient, case period was defined as 24 hour period preceding the time of emergency admission and referent periods were defined as the corresponding time in 1, 2, and 3 weeks before the admission. The associations of particulate matter with an aerodynamic diameter ≤2.5 µm (PM2 .5 ) and particulate matter with an aerodynamic diameter ≤10 µm (PM10 ) with AMI were analyzed using conditional logistic regression in a case-crossover design. RESULT: Increase in PM2.5 and PM10 was significantly associated with the occurrence of AMI with and without adjustment for the temperature and humidity. In the adjusted model each 10 µg/m3 increase of PM10 and PM2.5 in case periods was significantly associated with increase myocardial infarction events (95% CI = 1.041-1.099, OR = 1.069 and 95% CI = 1.073-1.196, and OR = 1.133, respectively). Subgroup analysis showed that increase in PM10 did not increase AMI events in diabetic subgroup, but in all other subgroups PM10 and PM2 .5 concentration showed positive associations with increased AMI events. CONCLUSION: Acute exposure to ambient air pollution was associated with increased risk of AMI irrespective of temperature and humidity.

Aortic dissection and Covid-19; a comprehensive systematic review.

Coronavirus disease 19 (Covid-19) has been declared as a pandemic disease since March 2020; causing wide array of signs and symptoms, many of which result in increased mortality rates worldwide. Although it was initially known as an acute respiratory disease, Covid-19 is accompanied with several extrapulmonary manifestations, of which the cardiovascular ones are of major importance. Among other cardiovascular complications of Covid-19, aortic dissection has been a significant yet underrated problem. The pathophysiology of aortic dissection consists of various inflammatory pathways, that could be influenced by Covid-19 infection. We herein have reviewed articles inclusive of aortic dissection concurrent with Covid-19 infection in a systematic manner, along with the probable similarities in pathophysiology of aortic dissection with Covid-19 infection.

25-Hydroxy Vitamin D Level and Its Correlation with Mean Platelet Volume in Preeclampsia.

Background: Preeclampsia is one of the challenging complications of pregnancy, of which little is known about its etiology and pathogenesis. Many studies have shown higher mean platelet volume (MPV) in preeclamptic patients. Vitamin D deficiency is in association with larger-size platelets. Thus, we aimed to determine the correlation of vitamin D with MPV in preeclamptic patients. Methods: This prospective case-control study was conducted in two tertiary hospitals in Tehran, Iran. Overall, 85 preeclamptic pregnant women and 85 normotensive pregnant women were entered between 2017 and 2018. Serum vitamin D concentration (ng/ml) and MPV (femtoliter) were measured for all patients. Results: MPV was significantly higher in the cases compared to controls (10.59±1.08 vs 8.10±0.95, P=0.0001). In addition, serum vitamin D level in the preeclamptic group was significantly lower in compare to the control group (17.79±11.03 vs 30.24±12.49; P=0.0001). In multivariate logistic regression analysis, high age of mother (OR: 1.13; 95% CI: 1.01-1.27; P=0.03), low level of serum vitamin D (OR: 0.93; 95% CI: 0.87-0.99; P=0.02) and high MPV (OR: 8.83; 95% CI: 4.17-18.67; P=0.0001) were independent predictors of preeclampsia. Moreover, a correlation analysis revealed that vitamin D levels correlated negatively with MPV (r= -0.41, P<0.0001). Conclusion: Low levels of vitamin D in preeclamptic pregnancy are associated with higher platelet activity and thrombosis. In fact, the increment of MPV level might be a potential pathway for adverse outcomes of pregnancy including preeclampsia in the context of vitamin D deficiency.

The association between QTc, QTd, TPE, and fragmented QRS before and after PPCI with hospital mortality in STEMI patients.

INTRODUCTION: ST-elevation myocardial infarction (STEMI) is known to be associated with significant arrhythmia and consequent mortality. QT prolongation is a risk factor for arrhythmia in STEMI patients who underwent primary percutaneous coronary intervention (PPCI). The aim of this investigation was to evaluate the association of corrected QT interval (QTc), QT dispersion (QTd), T-wave peak to end (TPE), and fragmented QRS with mortality in these patients. METHODS: Eligible patients with the characteristic symptoms of STEMI who underwent PPCI were included. QTc, QTd, TPE, and fragmented QRS were measured before and after the PPCI. These predictors were compared between patients who died during hospitalization and discharged patients. RESULTS: After coronary angiography, 10 patients (4%) died during the hospitalization after PPCI. Comparing the non-survivers and discharged patients in terms of arrhythmia predictors showed that the mean QT dispersion and TPE before intervention were significantly higher in the non-survivors. Also, the number of patients who experienced fragmented QRS both before and after the intervention was significantly higher in the non-survivors. CONCLUSION: These data suggested that evaluating such arrhythmia predictors, especially before PPCI, could be used as a predictor of mortality in STEMI patients who underwent PPCI.

Comparison of Outcomes with Midodrine and Fludrocortisone for Objective Recurrence in Treating Syncope (COMFORTS trial): Rationale and design for a multi-center randomized controlled trial.

BACKGROUND: The cornerstone of the treatment of vasovagal syncope (VVS) is lifestyle modifications; however, some patients incur life-disturbing attacks despite compliance with these treatments which underscores the importance of pharmacological interventions. METHODS: In this open-label multi-center randomized controlled trial, we are going to randomize 1375 patients with VVS who had ≥2 syncopal episodes in the last year into three parallel arms with a 2:2:1 ratio to receive midodrine, fludrocortisone, or no medication. All patients will be recommended to drink 2 to 3 liters of fluids per day, consume 10 grams of NaCl per day, and practice counter-pressure maneuvers. In medication arms, patients will start on 5 mg of midodrine TDS or 0.05 mg of fludrocortisone BD. After one week the dosage will be up-titrated to midodrine 30 mg/day and fludrocortisone 0.2 mg/day. Patient tolerance will be the principal guide to dosage adjustments. We will follow-up the patients on 3, 6, 9, and 12 months after randomization. The primary outcome is the time to first syncopal episode. Secondary outcomes include the recurrence rate of VVS, time interval between first and second episodes, changes in quality of life (QoL), and major and minor adverse drug reactions. QoL will be examined by the 36-Item Short Form Survey questionnaire at enrollment and 12 months after randomization. CONCLUSION: The COMFORTS trial is the first study that aims to make a head-to-head comparison between midodrine and fludrocortisone, against a background of lifestyle modifications for preventing recurrences of VVS and improving QoL in patients with VVS.

Effect of COVID-19 medications on corrected QT interval and induction of torsade de pointes: Results of a multicenter national survey.

BACKGROUND: There are some data showing that repurposed drugs used for the Coronavirus disease-19 (COVID-19) have potential to increase the risk of QTc prolongation and torsade de pointes (TdP), and these arrhythmic side effects have not been adequately addressed in COVID-19 patients treated with these repurposed medications. METHODS: This is the prospective study of 2403 patients hospitalised at 13 hospitals within the COVID-19 epicentres of the Iran. These patients were treated with chloroquine, hydroxychloroquine, lopinavir/ritonavir, atazanavir/ritonavir, oseltamivir, favipiravir and remdesivir alone or in combination with azithromycin. The primary outcome of the study was incidence of critical QTc prolongation, and secondary outcomes were incidences of TdP and death. RESULTS: Of the 2403 patients, 2365 met inclusion criteria. The primary outcome of QTc ≥ 500 ms and ∆QTc ≥ 60 ms was observed in 11.2% and 17.6% of the patients, respectively. The secondary outcomes of TdP and death were reported in 0.38% and 9.8% of the patients, respectively. The risk of critical QT prolongation increased in the presence of female gender, history of heart failure, treatment with hydroxychloroquine, azithromycin combination therapy, simultaneous furosemide or beta-blocker therapy and acute renal or hepatic dysfunction. However, the risk of TdP was predicted by treatment with lopinavir-ritonavir, simultaneous amiodarone or furosemide administration and hypokalaemia during treatment. CONCLUSION: This cohort showed significant QTc prolongation with all COVID-19 medications studied, however, life-threatening arrhythmia of TdP occurred rarely. Among the repurposed drugs studied, hydroxychloroquine or lopinavir-ritonavir alone or in combination with azithromycin clearly demonstrated to increase the risk of critical QT prolongation and/or TdP.

Air Pollution and Cardiac Arrhythmias: A Comprehensive Review.

Air pollution is the mixture of some chemical and environmental agents including dust, fumes, gases, particulate matters, and biological materials which can be harmful for the environment and the human body. The increasing trend of the air pollution, especially in developing countries, may exert its detrimental effects on human health. The potentially harmful effects of air pollution on the human health have been recognized and many epidemiological studies have clearly suggested the strong association between air pollution exposure and increased morbidities and mortalities. Air pollutants are classified into gaseous pollutants including carbon mono oxide, nitrogen oxides, ozone and sulfur dioxide, and particulate matters (PMs). All air pollutants have destructive effects on the health systems including cardiovascular system. Many studies have demonstrated the effect of air pollutant on the occurrence of ST elevation myocardial infarction, sudden cardiac death, cardiac arrythmias, and peripheral arterial disease. Recently, some studies suggested that air pollution may be associated with cardiac arrhythmias. In this study, we aimed to comprehensively review the last evidences related to the association of air pollutant and cardiac arrythmias. We found that particulate matters (PM10, PM2.5, and UFP) and gaseous air pollutants can exert undesirable effects on cardiac rhythms. Short-term and long-term exposure to the air pollutants can interact with the cardiac rhythms through oxidative stress, autonomic dysfunction, coagulation dysfunction, and inflammation. It seems that particulate matters, especially PM2.5 have stronger association with cardiac arrhythmias among all air pollutants. However, future studies are needed to confirm these results.

Acute type A aortic dissection in a patient with COVID-19.

The novel coronavirus spread all over the world in 2019 and became a serious international health concern of this century. Coronavirus disease 2019 (COVID-19) had a wide range of clinical manifestations; it can cause mild-to-severe multiorgan diseases, mostly affecting the respiratory system, but cardiovascular symptoms and complications are also frequently presented in COVID-19 patients. Herein, we report a type A aortic dissection in a confirmed case of COVID-19.

Left ventricular sphericity index analysis for the prediction of appropriate implantable cardioverter-defibrillator therapy.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) is the most effective therapy currently available to prevent sudden cardiac death (SCD) in patients with left ventricular (LV) dysfunction. Although LV ejection fraction (LVEF) is an excellent marker of SCD in these patients, determining other predictors might help to identify patients who will be benefit more from device implantation. The purpose of this study was to determine whether abnormal LV sphericity index (SI) in transthoracic echocardiography is associated with appropriate ICD therapy in these patients. METHODS: A total of 140 patients with primary ICD implantation (mean age 62.59 ± 11.36 years; 98 [70%] male) were included. The patients were classified into "no ICD therapy" or "ICD therapy" group according to the information of their devices for a maximum of 2 previous years. In four-chamber view image of transthoracic echocardiography, SI was calculated by dividing the major-axis dimension to minor-axis dimension of LV in both groups. RESULTS: Compared with patients with no ICD therapy, patients in ICD therapy group had lower LVEF (31.36 ± 9.58 vs 23.24 ± 6.03, P = 0.0001) and lower SI (1.79 ± 0.29 vs 1.57 ± 0.32, P = 0.0001). In multivariant logistic regression analysis, the SI of ≤1.58 was associated with fourfold increase of appropriate ICD therapy, even after adjusting for LVEF (odds ratio, 4.08; 95% confidence interval, 1.71-9.75; P = 0.02). CONCLUSION: Simple echocardiographic sphericity dimension index as a marker of cardiac remodeling may be an important predictor of appropriate ICD therapy in patients with primary prevention ICDs and may provide additive risk stratification in patients with LV systolic dysfunction.

The role of air pollution on ST-elevation myocardial infarction: a narrative mini review.

ST-elevation myocardial infarction (STEMI) is one of the potential causes of death worldwide. In spite of substantial advances in its diagnosis and treatment, STEMI is still considered as a major public health dilemma in developed and particularly developing countries. One of the triggering factors of STEMI is supposed to be air pollutants like gaseous pollutants including, sulfur dioxide, nitric dioxide, carbon monoxide, ozone and particulate matters (PM) including, PM under 2.5 µm (PM2.5) and PM under 10 µm (PM10). Air pollution can trigger STEMI with various mechanisms such as increasing inflammatory factors and changing the heart rate or blood viscosity. In this article, we aimed to explore research in the field and discuss the relationship between air pollution and STEMI.

Cardiogoniometry can predict positive response to cardiac resynchronization therapy - A proof of concept study.

BACKGROUND: According to American Heart Association guidelines, QRS duration and morphology are used to select patients for cardiac resynchronization therapy (CRT). But still there are some patients who are not responding to this device. We investigated whether the Cardiogoniometry (CGM) as a three-dimensional vectorcardiogram method can improve patient selection. METHODS: Echocardiography and CGM were performed for 25 consecutive patients with Left bundle branch morphology who were candidate for CRT implantation and were in sinus rhythm. Patients re-evaluated by echocardiography after 6 months post CRT implantation. RESULTS: The mean age of the patients was 63 ±â€¯13 years and 17 (68%) were males. The mean LVEF was 19.4 ±â€¯7.4% and 24.2 ±â€¯11.5% before and after CRT implantation respectively. Median of the duration of the R loop before the R maximum demonstrated a negative correlation with the increase in LVEF, (r = -0.36, P = 0.07) and mean of maximal spatial velocity of the T-loop for all measured showed a positive correlation (r = 0.39, p = 0.04). Other parameters didn't show any significant differences. CONCLUSIONS: Three-dimensional vectorcardiogram parameters can be helpful to predict the CRT response. Shorter duration of the R loop before the maximum R and smaller R loop area are predictors for responder patients.

The association between exposure to air pollutants including PM10, PM2.5, ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide concentration and the relative risk of developing STEMI: A case-crossover design.

BACKGROUND: Unfavorable associations between air pollution and myocardial infarction are broadly investigated in recent studies and some of them revealed considerable associations; however, controversies exists between these investigations with regard to culprit components of air pollution and significance of correlation between myocardial infarction risk and air pollution. METHODS: The association between exposure to PM10, PM2.5, ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide concentration of background air that residents of Tehran, the capital city of Iran, which is ranked as the most air polluted city of Iran and the relative risk of developing ST-elevation myocardial infarction (STEMI) were investigated by a case-crossover design. Our study included 208 patients admitted with a diagnosis of STEMI and undergone primary percutaneous intervention. Air pollutant concentration was averaged in 24-h windows preceding the time of onset of myocardial infarction for the case period. Besides, the mean level of each element of air pollution of the corresponding time in one week, two weeks and three weeks before onset of myocardial infarction, was averaged separately for each day as one control periods. Thus, 624 control periods were included in our investigation such that. Each patient is matched and compared with him/herself. RESULTS: The mean level of PM10 in case periods (61.47µg/m3) was significantly higher than its level in control periods (57.86µg/m3) (P-value = 0.019, 95% CI: 1.002-1.018, RR = 1.010). Also, the mean level of PM2.5 in case periods (95.40µg/m3) was significantly higher than that in control days (90.88µg/m3) (P-value = 0.044, 95% CI: 1.001-1.011, RR = 1.006). The level of other components including NO2, SO2, CO and O3 showed no significant differences between case and control periods. A 10µg/m3 increase in PM10 and PM2.5 would result in 10.10% and 10.06% increase in STEMI event, respectively. Furthermore, the results of sub-group analysis showed that older patients (equal or more than 60 year-old), diabetic patients, non-hypertensive ones and patients with more than one diseased vessel may be more vulnerable to the harmful effect of particular matters including PM10 and PM2.5 on development of STEMI. CONCLUSION: Air pollution is a worldwide pandemic with great potential to cause terrible events especially cardiovascular ones. PM2.5 and PM10 are amongst ambient air pollutant with a high risk of developing STEMI. Thus, more restrictive legislations should be applied to define a safe level of indoor and outdoor air pollutant production.

Valsalva maneuver using a Handmade Device in Supraventricular Tachycardia Reversion; a Quasi Experimental Study.

INTRODUCTION: The use of vagal nerve stimulation is identified as a proper treatment option in patients with stable supraventricular tachycardia (SVT). This study aimed to assess the success of Valsalva maneuver via a handmade device in reversion of SVT. METHODS: In this quasi experimental study, using a handmade device, vagus nerve stimulation was performed for SVT patients presenting to emergency department or cardiac intervention unit and the success rate and its related factors were assessed. RESULTS: 100 patients with the mean age of 53.05 ± 13.70 years were studied (67% female). 12 (12%) cases were unable to do the maneuver. Out of the 88 (88.0%) patients who could perform the maneuver, 75 (85.2%) cases were unsuccessful. Dysrhythmia was controlled in 6 (6.8%) cases on the first attempt and in 7 (8.0%) cases on the second one (14.8% total success rate). 12 of the 13 cases (92.3%) with successful maneuver had history of SVT (p = 0.031). There was not any significant association between success rate and sex (p = 0.084), age (p = 0.744), or other medical histories (p ≥ 0.05). CONCLUSION: Based on the results of the present study, the success rate of Valsalva maneuver with the mentioned handmade device was calculated to be 14.8%. The only independent related factor of successful reversion was SVT history.

Factors affecting ventriculophasic response: An investigation in patients with permanent pacemaker.

BACKGROUND: Ventriculophasic response (VR) refers to the shortening of the atrial cycle length (P-P-interval) that occurs during the heart block when a QRS complex is interposed between two P-waves. The aim of this study was to determine the factors affecting this phenomenon. METHODS: Thirty patients with high grade heart block treated with dual chamber pacemaker were studied. The pacer function of the patients' device was temporarily programmed to the ventricular-inhibited mode at 30 pulses per minute. A total of 330 recordings containing two P-waves with an interposed QRS and its previous P-P interval without any QRS were collected. The VR was defined as being present when the P-P interval with an interposed QRS shortened more than 3% compared to the preceding P-P interval. RESULTS: The VR was present in 45% of the recordings. In the multivariate logistic regression analysis, only a mid position of the interposed QRS was a positive predictor for presence of VR. However, there were no differences between recordings with or without VR groups according to QRS duration, paced or intrinsic interposed QRS. Hypertension and age had a negative correlation with the presence of VR when the QRS was interposed in the mid part. CONCLUSION: We found that the VR was present in approximately half of our cases. This phenomenon was mostly affected by position of the interposed QRS according to the previous P-P interval.

Upper extremity deep venous thrombosis and stenosis after implantation of pacemakers and defibrillators; A prospective study.

BACKGROUND: Obstruction of the access vein following cardiac pacemaker and defibrillator implantation is a common complication. However, the exact incidence and contributing risk factors are unknown. The aim of this study is to determine the incidence and analyze the contribution of each risk factor. METHODS: 57 consecutive patients candidate for their first transvenous pacemaker, implantable cardioverter-defibrillator (ICD), or cardiac resynchronization therapy device implantation were enrolled. After implantation, venography of the ipsilateral peripheral arm was performed. Patients underwent their second venography after the follow-up period of 3 to 6 months. RESULTS: 42 patients (13 females, mean age 59.71 ± 12.33) completed the study. The followup venography showed significant venous obstruction (more than 50%) in 9 (21%) patients, but in none of the individuals, venography revealed total occlusion of the veins. Patients with obstruction had more leads in their veins (2.56 ± 0.53 vs 1.58 ± 0.71, P = 0.001). Venous obstruction was significantly more prevalent in patients with implanted cardiac resynchronization therapy device compared with an ICD or pacemaker (p = 0. 01). Age, gender, diabetes mellitus, hypertension, ischemic heart disease and antiplatelet consumption did not reveal any other contribution to the risk of thrombosis. In multivariate analysis, total lead number was a positive predictor for venous occlusion (P = 0.015, OR:19.2, and CI: 1.7-207.1). CONCLUSION: Venous obstruction is relatively frequent after pacemaker or ICD implantation. This study also shows that pacemaker and ICD leads have a similar risk for lead-related venous obstruction. However, patients with multiple leads are associated with an increased risk.

Identification and management of right ventricular perforation using pacemaker and cardioverter-defibrillator leads: A case series and mini review.

Right ventricular perforation is a rare but serious complication of permanent pacemaker and implantable cardioverter-defibrillator implantation, with a reported prevalence rate of 0.1-6%. Generally, there is a high incidence of asymptomatic lead perforation with otherwise normal function. Some patients present with a stabbing chest pain and shortness of breath or pacemaker malfunction. However, in some cases, tamponade or adjacent tissue injury may be seen. The exact risk factors for lead perforation are not yet clear. Furthermore, there are many controversies in the management of lead perforation. Extraction of an asymptomatic, incidentally detected, chronically perforating lead does not seem to be necessary. Patients with symptoms or device malfunction will require treatment appropriate for their problem.

AV nodal reentrant tachycardia with a 2:1 right bundle branch block missed as bidirectional ventricular tachycardia in the first superficial evaluation.

A 95-year old woman was admitted to our emergency unit because of acute abdominal pain. After urgent surgery according to the acute abdomen, she was referred to intensive care unit (ICU) of the emergency unit as she was intubated. It was developed a run of new arrhythmia which was diagnosed by cardiology resident as bidirectional ventricular tachycardia due to beat to beat changing the axis of the QRS. However, a second and more precise evaluation of the abnormal ECG suggested a narrow supraventricular tachycardia, most probably AV nodal reentrant tachycardia with a 2:1 right bundle branch block.

The Assessment of short-term effect of L-Citrulline on endothelial function via FMD to NMD ratio in known CAD patients: A randomized, cross-over clinical trial (Clinical trial number: NCT02638727).

BACKGROUND: Recent studies have confirmed the essential and paramount role of the L-Citrulline on the nitric oxide regulation and the endothelial function improvement. MATERIALS AND METHODS: In this cross-over clinical trial, thirty patients, diagnosed with coronary artery disease (CAD) and flow mediated dilation to nitroglycerin dependent vasodilation (FMD/NMD) ratio less than 1, were included. The patients were randomly divided into two groups of 15 patients and underwent treatment by L-Citrulline or placebo for 15 days, in 2 step protocol. The indicators of assessment in the current study were the ratio of the FMD/NMD and FMD value. RESULTS: In the current cross-over clinical trial, the mean of FMD to NMD ratio and mean FMD value of all patients before starting the protocol were 0.91 ± 0.08 and 4.04 ± 0.51 mm, respectively. The final results of study showed that following L-Citrulline administration, mean FMD to NMD ratio and mean FMD value were enhanced to: 1.03 ± 0.09 and 4.96 ± 0.72 mm, respectively, which were statistically significant (P<0.001 and P<0.001, respectively). However, following placebo administration, mean FMD to NMD ratio and mean FMD value were receded to: 0.92 ± 0.09 and 4.06 ± 0.22 mm, respectively, which were not statistically significant (P = 0.75 and P = 0.89, respectively). Moreover, the improvement of mean FMD to NMD ratio (0.12 ± 0.02) and mean FMD value (0.92 ± 0.16 mm), following L-Citrulline administration, were statistically significant in comparison with the change of mean FMD to NMD ratio (0.01 ± 0.002) and mean FMD value (0.02 ± 0.003), following placebo administration (P<0.001 and P<0.001, respectively). CONCLUSION: L-Citrulline treatment can lead to improvement of the endothelial function in patients diagnosed with CAD which are assessed via FMD to NMD ratio FMD value enhancements.