Kostas Kappos

Detection of Myocardial Viability in the Prediction of Improvement in Left Ventricular Function After Successful Coronary Revascularization by Using the Dobutamine Stress Echocardiography and Quantitative SPECT Rest-Redistribution-Reinjection 201TI Imaging After Dipyridamole Infusion

The aim of this study was to assess the feasibility, safety, and respective diagnostic accuracy of low-dose dobutamine infusion and rest-redistribution-reinjection thallium 201 single photon emission computed tomography (SPECT) after dipyridamole infusion (Th-DIP), in the prediction of functional improvement of asynergic infarcted zones, after successful revascularization in patients with chronic ischemic heart disease. Thirty-one patients with a previous myocardial infarction and left ventricular dysfunction (mean ejection fraction: 41 ±5.8%) were studied. The regional wall motion of the left ventricle was evaluated by basic echocardiography before and 14 ± 1.7 weeks after successful revascularization (19 by percutaneous transluminal coronary angioplasty and 12 by coronary artery bypass grafting). Dobutamine stress echocardiography (DSE) was performed in all patients with dobutamine infusion of 5 and 10 μg/kg/minute over five minutes. Within three days after DSE and prior to revascularization, all patients underwent Th-DIP for myocardial viability assessment. A 16-ventricular-segment model was used for basic, DSE, and Th-DIP images. Viability was assessed by applying the (continued on next page) standard criteria for each technique. In the 31 patients, 496 segments were analyzed. By basic echocardiography, 164 (33%) of them were classified as asynergic. The DSE detected viable tissue in 69/496 (14%) segments, whereas Th-DIP identified viability in 95/496 (19%) segments. When the postrevascularization basic echocardiographic study was used as the gold standard in identifying myocardial viability, the sensitivity and specificity for the DSE and Th-DIP were 86.5%, 94.4% and 90.5%, 69%, respectively. No major side effects were observed with both techniques. In conclusion, DSE seems to be an accurate method for identifying viable but asynergic myocardium in patients with chronic ischemic heart disease, whereas Th-DIP overestimates the postrevascularization recovery. Detection of hibernating myocardium can be obtained by these two noninvasive methods. However, DSE seems to be more useful in determining the prospective selection of patients who are going to benefit from revascularization.

Effects of Magnesium and Potassium on Wolff-Parkinson- White Syndrome

To investigate the effects of electrolytes on anterograde conduction via accessory pathways, 12 patients with Wolff-Parkinson-White syndrome received, while in sinus rhythm, intravenous KCl (7 mEq in 200 mL of 0.9% NaCl), MgSO4 (10 mL 20% in 200 mL of 0.9% NaCl), NaCl (0.9%, 200 mL), and procainamide (maximal dose, 10 mg/kg of body weight over a 5-minute period) in a randomized fashion. NaCl had no effect on preexcitation. Procainamide abolished preexcitation in seven patients, of whom five had a similar response with MgSO4 and four with KCl. The finding that potassium and magnesium transiently abolish preexcitation in some Wolff-Parkinson-White patients deserves further study, especially during tachyarrhythmias in patients with accessory pathways.

Wide-QRS-Complex Tachycardia with a Negative Concordance Pattern in the Precordial Leads: Are the ECG Criteria Always Reliable?

We present a case of wide‐complex tachycardia with negative concordance in the precordial leads and a qR pattern in V6, in a 42‐year‐old man with risk factors for coronary artery disease, in whom the electrocardiogram criteria were apparently fallible. This case highlights the key contribution of the electrophysiological study in rendering correct diagnosis.

Mitral Regurgitation Protects from Left Atrial Thrombogenesis in Patients with Mitral Valve Disease and Atrial Fibrillation

The aim of this study was to test the hypothesis that mitral regurgitation (MR) has a protective effect on the development of left atrial thrombus (LAT) in patients with rheumatic heart disease and atrial fibrillation (AF). The study population consisted of 48 anticoagulated patients (mean age = 57.1 ± 10 years). Predominant mitral stenosis (MS) was present in 14 patients, predominant MR in 14, and a mechanical valve in 20. All patients underwent detailed transesophageal echocardiography. Severity of MR was based on measurements of the MR jet by color flow mapping. Patients were divided into two groups: (a) those with MR ≥ 3 + (n =12, 25%), and (b) those without significant MR (n = 36, 75%). A LAT was found in six patients (12.5%), who also had spontaneous echo contrast (SEC), while another group of 30 patients (62.5%) had SEC only. LAT and/or SEC were present in 2/12 patients (16.6%) with significant MR versus 34/36 patients (94.4%) without significant MR (P < 0.001). In addition to the absence of significant MR, left atrial diameter (LAD) > 60 mm, and severity of MS were also related to the presence of thrombus and/or SEC. Significant MR had a protective effect against thromboembolism, although this effect was abolished if LAD > 60 mm was present. In conclusion, in patients with mitral valve disease and AF, significant MR protects against LAT formation and systemic embolization. This protective effect was lost when LAD was > 60 mm.

Stress Echocardiography Using Adenosine Combined with Nitroglycerin- Dobutamine in the Detection of Viable Myocardium in Patients with Previous Myocardial Infarction

The aim of this study was to assess the value of adenosine (A) and the combination of nitroglycerin (N) with dobutamine (D) stress echocardiography (SE) in the identification of viable myocardium. The clinical and electrocardiographic (ECG) effects of both tests were also evaluated. Fifty-two coronary artery disease patients, aged 56.4 ±8 years, with left ventricular dysfunction due to a previous myocardial infarction (mean ejection fraction: 49 ±8%) were included in the study. Cardiac catheterization was performed in all patients before A (140 μg/kg/minute for five minutes) and the combination of N with D (5-10 μg/kg/minute) stress echocardiography. On the echocardiogram, the left ventricle was divided into 16 segments and wall motion was graded semiquantitatively from 1 (normal) to 4 (dyskinesia). The echocardiographic index was also estimated. A segment was considered viable during A infusion when resting asynergy showed deterioration of one grade or more. In contrast, segmental viability was considered to be present during the combination of N with D infusion when resting asynergy showed improvement of one grade or more. A thallium 201 single photon emission computed tomography (SPECT) with reinjection was performed as reference standard for the identification of viable myocardium. Stress echocardiography during infusion of A was associated with short-duration angina attacks in 3 (5.8%) patients and transient complete atrioventricular (AV) block in 1 (1.9%), whereas during the combination of N with D infusion, 6 (11.5%) patients expe rienced ventricular bigeminy lasting for a short period. ST segment elevation greater than 1 mm was recorded in those leads having a Q wave, in 19 (36.5%) patients. In 10 of these 19 (52.6%), viable myocardium was present in SPECT, as it was in 33 patients (63.5%) having no ST segment elevation (P=NS). Of a total of 832 segments that were graded during A-SE, 276 exhibited resting asynergy and the remaining 556 had normal motion and thickening at rest. The echocardiographic index during A infusion increased from 1.52 ±0.22 to 1.71 ±0.24 (P < 0.001), whereas during D and N infusion it decreased from 1.53 ±0.31 to 1.30 ±0.42 (P < 0.001). With SPECT considered as the gold standard for the identification of viable myocardium, sensitivity, specificity, and positive and negative predictive values of A-SE in detecting viable myocardium were 54%, 86%, 65% and 80%, respectively. The respective values for the combination of nitroglycerin with D-SE were 91%, 89%, 78%, and 96%, respectively. Stress echocardiography during A, and the combination of N with D, constitute safe methods in the identification of viable myocardium. The detection of ST segment elevation in the ECG leads with a Q wave during the combined infusion of nitroglycerin and dobutamine is not related to the presence of viable myocardial tissue. The A-SE provide moderate diagnostic accuracy, while the combination of N with D during SE is much superior in detecting viable myocardium.

Non-invasive evaluation of coronary reserve Assessment of coronary reserve in patients with coronary artery disease by transesophageal-Doppler echocardiography

We assessed coronary flow reserve using transesophageal Doppler echocardiography in patients with coronary artery disease. The study included 33 coronary artery disease patients who were undergoing coronary arteriography. The blood flow velocities of the left anterior descending artery before and after intravenous infusion (0.56 mg/min for 4 min) of dipyridamole were recorded using transesophageal Doppler echocardiography. Fourteen normal healthy individuals, matched for age, served as a control group. The index of coronary flow reserve, i.e. the ratio of dipyridamole to baseline maximum diastolic velocity, was calculated. Maximal coronary flow reserve in coronary artery disease patients was significantly lower than in the control group (1.4+/-0.2 vs. 2.8+/-0.3, P<0.001). The coronary artery disease patients were classified into three groups: Group A included 10 patients with <50% left anterior descending artery stenosis; Group B included seven patients with 50-69% left anterior descending artery stenosis; 16 patients with >70% left anterior descending artery stenosis constituted Group C. The maximum coronary flow reserve was significantly different for A vs. B and A vs. C. (A, 1.77+/-0.18; B, 1.51+/-0.1; C, 1.28+/-0.24). A strong and significant correlation was found between the maximum coronary flow reserve and the degree of proximal left anterior descending artery stenosis (r=0.78, P<0.001). Coronary artery disease patients without left anterior descending artery stenosis on the arteriogram exhibited lower maximum coronary flow reserve compared to the control subjects (1.78+/-0.19 vs. 2.8+/-0.3, P=0.000).

Parasystolic ventricular tachycardia with exit block

A rare case of parasystolic ventricular tachycardia with variable exit block concurring with runs of reentrant ventricular tachycardia is described. The reentrant ventricular tachycardia or isolated ventricular extrabeats modified the exit block patterns of the parasystolic tachycardia.

Ivabradine: a Selective If Current Inhibitor in the Treatment of Stable Angina

The role of heart rate reduction in the management of myocardial ischemia and chronic stable angina is pivotal. However, broad use and appropriate dosing of commonly used rate-slowing drugs is limited by their poor tolerability. Ivabradine is a selective inhibitor of the If currents of the sinoatrial node cells. If currents activity determines the slope of the depolarization curve towards the threshold level controlling heart rate in patients with sinus rhythm. Ivabradine, a compound of the benzocyclobutane (S 16257), exhibits a unique specificity for the If current and has a more favorable profile of adverse reactions compared to other If inhibitors. Accordingly, ivabradine has been used in the treatment of stable angina, where it presented anti-anginal and anti-ischemic effects equivalent to the effects of atenolol and amlodipine. Clinical studies proved the efficacy of ivabradine in patients with stable angina, while clinical data are awaited to verify its probable value in the treatment of atrial tachyarrhythmias and tachycardia due to ventricular dysfunction. Thus, the clinical value of ivabradine, which has completed clinical development for stable angina, is expected to exceed its role in the treatment of myocardial ischemia. In this context, ivabradine, promising efficacious and safe pharmacological management of heart rate, is a huge step in cardiovascular therapeutics.

Primary prevention of sudden cardiac death in Prinzmetal angina: The role of electrophysiology study in risk stratification

tp://dx.doi.org/10.1016/j.hjc.2016 09-9666/a 2016 Hellenic Cardiologi ense (http://creativecommons.org/ Myocardial ischemia during coronary vasospasm may provoke polymorphic ventricular tachycardia (pVT), which, in some cases, may degenerate into ventricular fibrillation (VF) and cause sudden cardiac death (SCD). Although spontaneous pVT during coronary vasospasm may well be explained as being triggered by ischemia, its induction during programmed ventricular stimulation (PVS) has not been adequately explored, and its association with the spontaneous occurrence of an arrhythmia remains dubious. We herein present a case of a patient with Prinzmetal angina who presented with spontaneous pVT, and who also had this arrhythmia reproducibly induced during an electrophysiology study (EPS), which was performed while the patient was under adequate medical therapy with no clinical or electrocardiographic evidence of ischemia. A 74-year-old man with a history of smoking and hypertension presented to his local hospital with typical substernal chest pain, which had resolved spontaneously after 5 min. The patient described recurrent similar episodes of pain during the preceding two months. The pain was related to emotional stress and smoking. His ECG on admission revealed nonspecific ST-T wave abnormalities (Figure 1A), and his cardiac troponin was negative. His echocardiography results were normal. He was admitted to

Techniques of Implantation of a Biventricular Pacing System

The present case report describes a patient who sustained an acute inferior wall myocardial infarction, but initially remained clinically stable, then he underwent a successful coronary angioplasty and stenting procedure of a totally occluded right coronary artery, subsequently developing a dramatic clinical course with cardiogenic shock and cardiac arrest due to acute stent thrombosis which was successfully managed with repeat coronary angioplasty. We attributed this discrepant clinical manifestation of acute coronary occlusion to coronary collaterals, initially being present and then disappearing following the recanalization procedure, as being responsible for the dramatic clinical picture following the stent thrombosis.Aim: The purpose of this investigation was to collect data on the appropriate nursing care to patients supported with an intra-aortic balloon pump (IABP).Patients: All 39 patients who were supported with an IABP during the year 2006 (23 men ??? 16 women) took part in this investigation. They received nursing and medical care in the Intensive Care Cardiovascular Unit (ICCU) of Evagelismos General Hospital of Athens.Πeριγράφeται η πeρίπτωση eνός ασθeνούς, 66 eτών, που παρουσιάσθηκe μe πολλαπλά eπeισόδια eμμένουσας μονόμορφης κοιλιακής ταχυκαρδίας 30 και 14 έτη μeτά δύο eμφράγματα του κατωτέρου και του προσθίου τοιχώματος του μυοκαρδίου. Αφού η ηλeκτρική θύeλλα κατeστάλη μe ένα μeικτό σχήμα τριπλής αντιαρρυθμικής αγωγής, ο ασθeνής υπeβλήθη σe eνδοκαρδιακή κατάλυση της αρρυθμιογόνου eστίας μe τη βοήθeια του ηλeκτροανατομικού συστήματος χαρτογράφησης στο ηλeκτροφυσιολογικό eργαστήριο. Ακολούθησe η eμφύτeυση eνός αντιταχυκαρδιακού βηματοδότου απινιδωτού που στους eπακόλουθους 30 μήνeς παρακολούθησης κινητοποιήθηκe αθόρυβα σe ένα μοναδικό στιγμιότυπο αντιταχυκαρδιακής βηματοδότησης.Ο όρος οξύ στeφανιαίο σύνδρομο ( ACS ) αναφέρeται σe ένα φάσμα τριών πιθανών κλινικών eκδηλώσeων της στeφανιαίας νόσου, την ασταθή στηθάγχη (UA), το έμφραγμα χωρίς ανάσπαση του ST (NSTEM) και το έμφραγμα μe ανάσπαση του ST (STEMI). Η διάκριση αυτή eίναι χρήσιμη στην ανάπτυξη θeραπeυτικών στρατηγικών. Το Αμeρικανικό κολλέγιο καρδιολογίας ( ACC ) και η Αμeρικανική καρδιολογική eταιρία ( AHA ), από κοινού δημοσιeύουν κατeυθυντήριeς οδηγίeς για την αντιμeτώπιση των οξέων στeφανιαίων συνδρόμων. Η τeλeυταία αναθeώρηση των προτeινόμeνων κατeυθυντήριων οδηγιών έγινe το 2007. Η ασταθής στηθάγχη ( UA ) και το NSTEMI έμφραγμα eίναι δύο δυσδιάκριτeς μeταξύ τους οντότητeς και η διαφορά τους έγκeιται στο γeγονός ότι το NSTEMI χαρακτηρίζeται από πeρισσότeρο eκτeταμένη μυοκαρδιακή βλάβη, μe απeλeυθέρωση στην κυκλοφορία τροπονίνης (TnT ή TnI ) ή CK-MB. Eίναι σημαντικό στην αντιμeτώπιση της ασταθούς στηθάγχης/NSTEMI να eπιλέξουμe πρώιμα ανάμeσα σe eπeμβατική ή συντηρητική θeραπeυτική στρατηγική. Η eπιλογή γίνeται μe βάση στοιχeία από το ιστορικό, την κλινική eικόνα και τα eργαστηριακά eυρήματα του ασθeνούς ... (excerpt)Despite primary and secondary methods for the prevention of acute coronary syndromes, there is still poor patient and physician understanding of the importance of smoking cessation. Cardiovascular risk decreases significantly after smoking cessation, however, there is a paucity of counseling programs regarding this issue after hospitalization. Such programs have proved to be cost effective and should be provided as standard care.