Periklis Davlouros

Interatrial conduction time and incident atrial fibrillation: a prospective cohort study.

BACKGROUND Atrial electrical conduction properties have been implicated in atrial fibrillation (AF) pathogenesis. OBJECTIVE The purpose of this study was to prospectively assess the potential association of interatrial conduction time (IACT) with incident AF. METHODS The study included persons referred for invasive electrophysiologic study (EPS), aged ≥50 years, without AF history or valvular disease. IACT was defined as the interval between the high right atrium electrogram and the distal coronary sinus atrial electrogram. RESULTS Six hundred twelve subjects were included (median follow-up 43 months, interquartile range 40-47). AF incidence was 21.7 cases per 1000 person-years. IACT was a significant predictor of AF with a c-statistic of 0.770 (95% confidence interval 0.702-0.838). In time-dependent analysis, IACT was a significant stratifier of AF risk (log-rank 28.0, P <.001). The corresponding incidences of AF in each tertile of IACT were 3, 17, and 46 per 1000 person-years, respectively (all differences between tertiles were significant). IACT remained significant in multivariable Cox regression analysis, after adjustment for age, sex, hypertension, and left atrial diameter, with each millisecond of prolonged IACT corresponding to 7% (95% confidence interval 2%-12%) higher adjusted risk of incident AF. CONCLUSION IACT is independently associated with incident AF. The invasive nature of the measurement is a limitation for its use as a clinical risk stratifier (although it could be used in patients referred for EPS), but these results are of interest in themselves because they suggest a strong pathophysiologic connection between atrial conduction times and substrate alterations ultimately leading to AF.

Combined etiology of anaphylactic cardiogenic shock: amiodarone, epinephrine, cardioverter defibrillator, left ventricular assist devices and the Kounis syndrome.

Anaphylactic shock is a life-threatening condition which needs detailed and mediculous clinical assessment and thoughtful treatment. Several causes can join forces in order to degranulate mast cells. Amiodarone which is an iodine-containing highly lipophilic benzofuran can induce allergic reactions and anaphylactic shock in sensitized patients. Epinephrine is a life saving drug, but in sulfite allergic patients it should be given with caution due its metabisulfite preservative. Metals covering cardiac defibrillators and pacemakers can act as antigens attached to serum proteins and induce allergic reactions. In anaphylactic shock, myocardial involvement due to vasospasm-induced coronary blood flow reduction manifesting as Kounis syndrome should be always considered. Clinically, combined treatment targeting the primary cause of anaphylaxis together with protection of cardiac tissue seems to be of paramount importance.

Effects of two nebulization regimens on heart rate variability during acute asthma exacerbations in children.

Analysis of heart rate variability (HRV) has been used to evaluate changes in sympathovagal balance. The present study was designed to investigate the influence of two therapeutic regimens on autonomic cardiovascular regulation during acute asthma exacerbations (AAE). Twenty children, 7–13 years of age, with moderate or severe AAE were randomized in two equal groups to receive either 0.15 mg/kg/dose salbutamol (group 1) or a combination of lower-dose salbutamol (0.10 mg/kg/dose) and ipratropium bromide (5 mcg/kg/dose) (group 2). Exacerbations were treated with three nebulizations (Tx) of either regimen given 20 minutes apart. HRV indices [total power, high-frequency component (HF), low-frequency component (LF), and LF:HF ratio] were analyzed at specific time intervals during the management of AAE. Therapy had a significant time-dependent main effect on total power (p = 0.001), LF (p < 0.0001), and HF (p = 0.005) but reached only borderline significance for LF:HF ratio (p = 0.053). The decrease in LF was more pronounced in group 2 vs. group 1 at 10 minutes post-Tx1 (p = 0.034) and at 10 minutes post-Tx2 (p = 0.05), but there was no significant difference between groups at 10 and 20 minutes post-Tx3. There were no significant differences between groups in any of the other HRV indices. Both regimens improved FEV1 (p = 0.0001) to the same magnitude. During AAE, three consecutive inhalation treatments with either high-dose salbutamol-only or lower-dose salbutamol plus ipratropium bromide combination, resulting in similar FEV1 improvement, cause domination of sympathetic over parasympathetic nervous system of similar overall magnitude but distinct patterns of HRV indices.

46 Serum BNP and Clinical Outcomes Prediction in Tetralogy of Fallot: A Prospective Analysis

Background Neurohormonal activation has been demonstrated in small cross-sectional studies in congenital heart disease. Brain natriuretic peptide(BNP) levels have been shown to be elevated in repaired Tetralogy of Fallot (rTOF) patients when compared to controls. Whilst serum BNP measurement measurement has long been used in the clinical management of heart failure patients with left ventricular pathology, its relevance and longitudinal predictive value of adverse clinical outcomes in rTOF is unknown. Methods rTOF patients aged over 16 years with no contra-indications to cardiovascular magnetic resonance (CMR) were prospectively recruited at an adult congenital heart disease tertiary centre (September 2000–March 2004). Study participants had baseline observations, ECG, chest radiographs, CMR and peripheral blood sampling for neurohormone quantification in accordance with study protocol (with local ethics approval). Age- and gender-matched healthy controls were also recruited with peripheral blood neurohormone quantification and baseline observations recorded. Follow-up data was collated from hospital medical records, with mortality status obtained from the Office for National Statistics (UK). The primary endpoint was all cause mortality. Results Ninety rTOF patients (mean age 32.7 ± 11.3 years, 58 males) and 15 matched controls (mean age 30.3 ± 5.0 years, 7 males) were included. rTOF patients had elevated levels of BNP (15.6 ± 26.9 vs 5.3 ± 3.4pmol/l, p < 0.01), ANP (12.2 ± 23.1 vs 3.5 ± 2.6 pmol/l, p < 0.05), Endothelin-1 (1.23 ± 0.42 vs 0.82 ± 0.49 pmol/l, p < 0.01) and renin (60.7 ± 41.7 vs 16.3 ± 7.5pmol/l, p < 0.01). Sixty-four (71%) study participants were asymptomatic, with 80 (89%) having abnormal BNP levels (>4 pmol/l) at baseline. Symptomatic rTOF patients had significantly higher levels of neurohormones (Table 1). Abstract 46 Table 1 Neurohormonal activation and symptoms in rTOF patients vs. controls Outcome data was available for 83 patients over a median follow-up of 10 years (IQR 0.71–12.4 years, 4 patients emigrated, 3 patients defaulted from clinical follow-up). There were 7 deaths (2 sudden cardiac deaths, 2 peri-operative right ventricular failure, 1 concomitant severe aortic stenosis, 1 respiratory sepsis and 1 unknown). BNP was significantly related to all cause mortality on univariate Cox proportional hazards analysis (AUC 0.68 with ROC characteristics analysis, logrank p = 0.04; Figure 1), in addition to other recognised adverse markers of clinical outcomes including cardiothoracic ratio, creatinine and right atrial area (Table 2). Abstract 46 Figure 1 (a) Kaplan-Meier survival curve for BNP (b) Univariate predictors of mortality in rTOF Conclusions In this large, prospective series with long-term follow-up data, BNP was elevated even in asymptomatic rTOF patients and was predictive of mortality. The measurement of BNP in rTOF patients has clinical utility for risk stratification during lifelong care.

Supernumerary Umbilical Vein in a Hydropic Neonate with Hypertrophic Cardiomyopathy

The anomalies of the umbilical vessels are uncommon, with the exception of a single umbilical artery. We report a term female infant with fetal hydrops, hypertrophic cardiomyopathy, and a four-vessel umbilical cord consisting of two umbilical arteries and two umbilical veins. The presence of two veins in the umbilical cord has been attributed to persistence of both the normal left umbilical vein and the caudal part of the right umbilical vein. This fetal vascular pathology has been reported very rarely and may be associated with increased risk of congenital malformations and adverse perinatal outcome.

Coronary calcium detected by digital cinefluoroscopy and coronary artery disease in patients undergoing coronary arteriography: effects of age and sex

BACKGROUND Coronary artery calcium, detected non-invasively, correlates well with angiographically documented coronary artery disease (CAD). This study was conducted to evaluate the diagnostic efficacy of coronary artery calcium detected by digital cinefluoroscopy for CAD and assess the effects of age and sex on it. METHODS In 242 patients who underwent coronary angiography, coronary calcium status was determined and related to angiographic findings. RESULTS Calcium detection had a sensitivity 85%, specificity 52%, positive predictive value 92%, negative predictive value 33% and diagnostic accuracy 81% for significant CAD. There was a better positive predictive value in men (95% vs. 80%) and negative predictive value in women (65% vs. 16%), while a higher sensitivity and diagnostic accuracy was found in older than in younger (90% and 86% vs. 78% and 74%). The sensitivity of the method increased with the number of the diseased vessels. CONCLUSIONS Coronary calcium can be quite accurately detected by digital cinefluoroscopy. This, however, should be made in the context of sex and age.

Needle versus cannula over needle for radial artery cannulation during transradial coronary angiography and interventions

PURPOSE To evaluate the efficacy of radial artery cannulation with needle versus cannula over needle during transradial coronary angiography and intervention. METHODS Five hundred patients scheduled to undergo transradial catheterization were randomized between the two methods. Primary endpoint of the study was the combined endpoint of switching to another access site due to inability of successful sheath insertion or switching to another method of cannulation (from needle to cannula over needle and vice versa). RESULTS The primary end point was met in 12 patients (4.8%) from the needle group and 14 patients (5.6%) from the cannula over needle group (p=0.695). There were no differences in switching of cannulation method [10 (4.0%)% versus 11 (4.4%), p=0.831], switching of access site [6 (2.8%) versus 9 (3.6%), p=0.441), time for artery cannulation [1.20 (0.80-2.20) min versus 1.26 (1.01-2.39) min, p=0.152], total procedure time [15.05 (9.47-29.03) min versus 19.14 (10.13-32.02) min, p=0.112] number of attempts [2 (1-4) versus 2 (1-5), p=0.244] and number of skin punctures [1 (1-2) versus 1 (1-2), p=0.399] before successful radial artery cannulation. There were no differences recorded in the safety endpoints of EASY grade III or more radial hematomas [2 (0.8%) versus 1 (0.4%), p=1.000] or the incidence of radial artery occlusion after the procedure [9 (3.6% versus 16 (6.8%), p=0.358]. CONCLUSION Radial artery cannulation with needle and cannula over needle seems to be equal in terms of efficacy and safety.

Negative association between previous allergy and intradermal tests for rocuronium and cisatracurium: what about additional tests?

Anesthesiology [1] concerning the relationship between intradermal tests for neuromuscular blocking agents in patients with history of allergy to various anesthetic agents, no association between allergy history and positive skin test was found. This report raises the following important issues with respect to anaphylaxis during anesthesia, rocuronium-sugammadex complex, additive anaphylactic effect of anesthetic agents, and additional diagnostic tests in anesthesia: 1. Anaphylaxis during anesthesia constitutes a severe adverse event, rendering its identification and early treatment imperative. and partially explains its causality, pathophysiology, and mortality. The incidence of hypersensitivity reactions during anesthesia varies from 1 : 3,180 to 1 : 10,000 based on several prospective studies; however, this incidence might be underestimated [2]. Multiple causative factors have been implicated, including drugs, liquids, metal devices, materials, and procedures during anesthesia. The incidence of perioperative reactions in Spain was 1 : 381, involving mild skin reactions (48%) and cases of anaphylaxis (52%). On rare occasions, skin rash might be absent, as seen with drug reactions in eosinophilia and Kounis syndrome. 2. Sugammadex induces selective reversal of aminosteroidal non-depolarizing neuromuscular blockers acting as muscle relaxants, such as rocuronium and vecuronium. Sugammadex is a modified gamma cyclodextrin with eight carboxyl thio ether groups at the sixth carbon positions, creating a cavity that can encapsulate the rocuronium molecule and further produce the rocuronium-sugammadex complex. The rocuronium-sugammadex complex can induce anaphylactic reactions, and is also suggested to induce Kounis syndrome [3]. Notably, during anesthesia, patients may be exposed to various agents such as propofol, remifentanil, rocuronium, fentanyl, and sugammadex, all able to induce immunological changes. 3. In a recent report [4], a 46-year-old male patient developed tachycardia with ST elevation in the inferior leads and shock without cutaneous manifestations following propofol, remifentanil, rocuronium, fentanyl, and sugammadex administration during anesthesia for laparoscopic surgery. Two years later, a similar anaphylactic reaction occurred, this time accompanied by generalized erythema, following perioperative administration of rocuronium and sugammadex. Serum histamine and tryptase levels were increased, whereas skin prick tests were negative for rocuronium and sugammadex but positive for histamine and rocuronium-sugammadex complex. The authors wondered how rocuronium-sugammadex complex formation could induce imLetter to the Editor

Device thrombosis in continuous-flow left ventricular assist devices: A new manifestation of Kounis syndrome?

1. Noris M, Caprioli J, Bresin E, et al. Relative role of genetic complement abnormalities in sporadic and familial aHUS and their impact on clinical phenotype. Clin J Am Soc Nephrol 2010;5:1844-59. 2. Galli FC, Damon LE, Tomlanovich SJ, et al. Cyclosporine-induced hemolytic uremic syndrome in a heart transplant recipient. J Heart Lung Transplant 1993;12:440-4. 3. Myers JN, Shabshab SF, Burton NA, et al. Successful use of cyclosporine in a lung transplant recipient with tacrolimus-associated hemolytic uremic syndrome. J Heart Lung Transplant 1999;18:1024-6. 4. Noris M, Remuzzi G. Atypical hemolytic-uremic syndrome. N Engl J Med 2009;361:1676-87.

Bleeding complication with dual antiplatelet therapy: spontaneous uvula hematoma

An 81-year-old man with a history of coronary artery disease experienced a sudden choking feeling, sore throat, difficulty swallowing and itchy mouth immediately after finishing dinner. He was taking clopidogrel 75 mg combined with 100 mg acetylsalicylic acid once daily, and metoprolol tartrate 50