Complex fractionated atrial electrograms at anatomic sites of ganglionated plexi in atrial fibrillation.

AIMS: To investigate the relationship of complex fractionated atrial electrograms (CFAEs) with the activity of the ganglionated plexi (GP) in the cardiac autonomic nervous system. METHODS AND RESULTS: Thirty-two patients (aged 55 +/- 10 years, five females) scheduled for circumferential ablation for paroxysmal atrial fibrillation (AF) were studied. Mapping of CFAEs during AF was performed at the left atrium (LA) and pulmonary vein-atrial junctions, particularly at the locations where GP are commonly located. Complex fractionated atrial electrograms were identified at >or=1 GP site in 22 of 32 patients (68.8%) and >or=1 LA wall site in 11 patients (34.4%, P < 0.001). In the 10 patients without CFAEs at the GP site, only one patient displayed CFAEs at the LA site. At the site of the left superior GP, CFAEs were recorded in 17 of 32 patients (53.1%), and in 14 (43.8%), 10 (31.3%), 13 (40.6%), and 19 (59.4%) patients at the sites of left inferior, right anterior, right inferior GP, and crux GP, respectively. Ten of 11 patients with CFAEs recorded in the LA wall also displayed CFAE in at least one GP. This association was statistically significant (P = 0.05). In 7 of these 11 patients, CFAEs were also recorded in the LA wall sites adjacent to a GP that also displayed CFAEs. CONCLUSION: Complex fractionated atrial electrograms at presumed anatomic sites of GP were identified in 68.8% patients with paroxysmal AF. In 11 patients without CFAE at the GP, CFAEs were recorded in the LA wall only in one patient. These findings suggest an association between CFAEs and GP.

Three-dimensional analysis of the left anterior descending coronary artery: comparison with conventional coronary angiograms.

OBJECTIVE: This study aimed at comparing three-dimensional (3-D) reconstruction with two-dimensional coronary angiograms with respect to anatomical parameters that might affect plaque formation and rupture. METHODS: Sixty patients with stable left anterior descending (LAD) lesions and 60 patients with an anteroseptal myocardial infarction and recanalized LAD were studied. RESULTS: Conventional angiography significantly underestimated the distance of the stenosis from the ostium of the LAD, 29.4+/-14.5 versus 35.3+/-18.5 mm, P<0.001. Vessel curvature at the site of the lesion was overestimated by conventional angiography compared with 3-D reconstruction, 147.6+/-30.6 degrees versus 162.3+/-11.2 degrees , P<0.001, as was axial bending of the LAD owing to ventricular contraction (17.8+/-7.78 degrees vs. 8.9+/-8.9 degrees , P<0.001). No agreement was observed between two-dimensional and 3-D analysis for either curvature on lesion or axial bending assessment, with intraclass correlation coefficient values 0.155 (-0.009, 0.315) and -0.022 (-0.183, 0.174), respectively. No significant agreement was found between the two methods in the detection of on-stenosis bifurcations (1.7%, kappa=0.086, P=0.349). CONCLUSION: Conventional coronary angiography cannot provide accurate estimates of anatomical parameters, such as distance of a coronary stenosis from the ostium of the vessel, coronary artery curvature at the site of stenosis, axial deformity and bending because of ventricular contraction, and classification of bifurcations. Reconstruction of the coronary tree in 3-D space is necessary for such estimations.

Association of neutrophil gelatinase-associated lipocalin with the severity of coronary artery disease.

Serum neutrophil gelatinase-associated lipocalin (NGAL) concentrations were measured in 73 consecutive patients who underwent first-time angiography for suspected coronary artery disease (CAD), and their associations with angiographic indexes of the severity of CAD (i.e., number of diseased vessels and modified Gensini score) were estimated. Median serum NGAL levels in patients with angiographically confirmed CAD were significantly higher than those in patients with normal coronary arteries (29.0 ng/ml [interquartile range 25.2 to 36.8] vs 22.4 ng/ml [interquartile range 17.34 to 32.0], p = 0.004). Statistically significant correlations were observed between serum NGAL level and the number of diseased vessels (r(s) = 0.390, p = 0.01) and modified Gensini score (r(s) = 0.356, p = 0.002). Using multivariate analysis, serum NGAL level was independently associated with the presence and severity of CAD. In conclusion, serum NGAL levels are significantly higher in the presence of CAD and are correlated with the severity of the disease. Further clinical studies are needed to confirm the use of NGAL as a biomarker for the detection and extent of CAD.

Comparison of long versus short ("spot") drug-eluting stenting for long coronary stenoses.

We compared spot drug-eluting stenting (DES) to full stent coverage for treatment of long coronary stenoses. Consecutive, consenting patients with a long (>20 mm) coronary lesion of nonuniform severity and indication for percutaneous coronary intervention were randomized to full stent coverage of the atherosclerotic lesion with multiple, overlapping stenting (full DES group, n = 90) or spot stenting of hemodynamically significant parts of the lesion only (defined as diameter stenosis >50%; spot DES group, n = 89). At 1-year follow-up, 14 patients with full DES (15.6%) and 5 patients (5.6%) with spot DES had a major adverse cardiac event (MACE; p = 0.031). At 3 years, MACEs occurred in 18 patients with full DES (20%) and 7 patients (7.8%) with spot DES (p = 0.019). Cox proportional hazard model showed that the risk for MACEs was almost 60% lower in patients with spot DES compared to those with full DES (hazard ratio 0.41, 95% confidence interval 0.17 to 0.98, p = 0.044). This association remained even after controlling for age, gender, lesion length, and type of stent used (hazard ratio 0.42, 95% confidence interval 0.17 to 1.00, p = 0.05). In conclusion, total lesion coverage with DES is not necessary in the presence of diffuse disease of nonuniform severity. Selective stenting of only the significantly stenosed parts of the lesion is an appropriate therapeutic alternative in this setting, offering a favorable clinical outcome.

Three-dimensional analysis of vulnerable segments in the left anterior descending artery.

OBJECTIVES: Analysis of conventional angiograms has suggested that specific anatomic parameters of particular segments of a coronary artery render them prone to vulnerable plaque development, plaque rupture, and consequent thrombosis. This study aimed at performing a three-dimensional analysis of recanalized left anterior descending (LAD) coronary arteries in patients who had suffered an anterior ST-elevation myocardial infarction (STEMI). METHODS: Coronary angiograms of 76 consecutive patients with an anterior STEMI and a recanalized LAD were reconstructed in the three-dimensional space, and compared with angiograms of 76 patients with stable coronary artery disease (SCAD) and significant LAD stenosis. RESULTS: In both groups the majority of lesions occurred between 20 and 40 mm (P=0.745), but the number of lesions beyond 60 mm from the ostium was significantly higher in SCAD compared with STEMI (P=0.045). Culprit lesions were statistically significantly longer in patients with STEMI compared with SCAD (18.3+/-7.5 vs. 12.7+/-6.2 mm, P<0.001). Cut-off point analysis indicated a lesion length of >or=12.5 mm as discriminating threshold between SCAD and STEMI (sensitivity 79% and specificity 63%). Bifurcation branches on the culprit lesion were seen in 79% of the patients with STEMI and 58% of those with SCAD (P=0.026). Lesion angulation was significantly sharper in STEMI compared with SCAD patients in diastole (155+/-15 vs. 160+/-14 degrees, P=0.037). Multiple logistic regression model including these parameters had a high discriminating ability with c-statistic 0.78 (95% confidence intervals: 0.71-0.86), sensitivity 72.4%, and specificity 75%. CONCLUSION: Specific anatomic characteristics of LAD segments predispose to development of plaque rupture and thrombosis.

Anatomic characteristics of culprit sites in acute coronary syndromes.

BACKGROUND: A detailed analysis of the anatomic relationships of the site of culprit lesions that have resulted in acute coronary syndromes (ACS) has not been reported. METHODS: Coronary angiograms of consecutive patients who presented with ACS were analyzed according to multiple anatomic criteria. RESULTS: In left anterior descending artery (LAD) (n = 85), 85% of culprit lesions were located in the first 40 mm from the ostium. The presence of angulation on the lesion increased the risk of an ACS 1.92 times (95% confidence interval [CI] 1.9-3.07), and the presence of bifurcation after the lesion increased the risk 1.65 times (95% CI 1.04-2.62). Angulated lesions located within the first 40 mm from the ostium and before a bifurcation presented an 11-fold increased risk for an ACS. In right coronary artery (RCA) (n = 58), the risk of plaque rupture was almost 2.5 times higher in lesions located between 10 and 50 mm from the ostium compared to those located in 90-130 mm (relative risk [RR] 2.38, 95% CI 1.25-4.56). In left circumflex (LCx) (n = 40), the risk of plaque rupture was almost 4.5 and 5 times higher in the first 20 mm, and between 20 and 40 mm from the ostium, respectively, compared to 60 and 80 mm (relative risk [RR] 4.58, 95% CI 1.01-20.68 for 0-20 mm, and RR 4.95, 95% CI 1.14-21.47 for 20-40 mm) after adjustment for the presence of curve on the lesion. The presence of lesion angulation increased the risk of plaque rupture almost three times (RR 3.22, 95% CI 1.49-6.93). CONCLUSION: Specific anatomic features of the coronary arteries predispose to development and/or subsequent rupture of vulnerable plaques.

Staged circumferential and ostial pulmonary vein ablation for the treatment of paroxysmal atrial fibrillation.

BACKGROUND: Comparisons between segmental ostial disconnection of the pulmonary veins (PV) and circumferential ablation have produced conflicting results in patients with paroxysmal atrial fibrillation (AF). The aim of this study was to evaluate a staged ablation procedure, every step of which was assessed by means of AF inducibility. METHODS: Twenty-two patients with paroxysmal AF were subjected to three ablation stages during one session: (1) circumferential ablation around the PV ostia, (2) segmental ostial PV isolation, and (3) ablation of areas within the circumferential lines with fractionated electrograms or voltage >0.2 mV as well as linear ablation at the mitral isthmus and the left atrial roof. Endpoint of the procedure was noninducibility of AF at any stage. RESULTS: Average radiofrequency energy delivery, fluoroscopy, and procedure times were 43 +/- 11 minutes, 40 +/- 11 minutes, and 3.8 +/- 0.5 hours, respectively. At 6-months follow-up, four patients experienced recurrence of AF (18%), whereas two additional patients (9%) had left atrial arrhythmias not registered before the procedure. Ninety-five percent of the patients who did not have inducible AF (regardless of the stage of ablation at which noninducibility was achieved) were free of recurrent AF, as opposed to none of the patients in whom AF was inducible at the end of the procedure (log-rank test, P < 0.001). CONCLUSIONS: A staged ablation procedure combing circumferential and ostial PV ablation with AF noninducibilty as endpoint may result in high success rates without the need of prolonged ablation sessions in certain patients with paroxysmal atrial fibrillation.

Sirolimus-versus paclitaxel-eluting stents: a comparison of two consecutive series in routine clinical practice.

BACKGROUND: We compared two consecutive series of patients treated with sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES). METHODS: Two hundred and ninety-five patients with 590 coronary lesions were treated with 274 SES and 379 PES. Patients with symptoms or positive dobutamine stress echocardiography were subjected to repeat coronary angiography. RESULTS: During a follow-up of 13.3 +/- 5.7 months, the incidence rate of major adverse cardiac events (MACE) was 4.1%, including, 1 death, 4 Q-wave myocardial infarctions, 2 late angiographic stent thromboses, 3 subacute stent thromboses, and 11 target vessel revascularizations (TVR), and was not significantly different between SES (n = 5) and PES (n = 7). Stent overlapping was found to be an independent predictor of both MACE (odds ratio = 0.078, P = 0.02) and TVR (odds ratio = 0.077, P = 0.02). Follow-up symptoms- or ischemia-driven angiography was performed in 45 patients. Only vessel size was a predictor of stent restenosis (P = 0.02), independent of stent type. Late loss was independently predicted by postdilatation of stent (beta =-0.24, P = 0.03), but not by type of stent (P = 0.14) or other parameters. Edge restenosis was seen in 8 patients subjected to lesion predilatation. The restenosis pattern after SES implantation was focal, but diffuse (n = 1) or proliferative (n = 1) restenosis, and in-stent aneurysm formation (n = 1) was also seen with PES. CONCLUSIONS: Despite a trend for a higher incidence of MACE with PES, no significant differences between the two stent types were detected. Diffuse restenosis was seen only with PES, and edge restenosis only in lesions with balloon predilatation before stent implantation. Stent overlapping was an independent predictor of both TVR and MACE.

Direct versus predilatation drug-eluting stenting: a randomized clinical trial.

BACKGROUND: Direct stenting without balloon predilatation has been shown to be feasible and safe with drug-eluting stents, but no randomized comparisons between the two strategies exist. This study was designed to compare direct stenting with balloon predilatation followed by stent placement using only drug-eluting stents. METHODS: One hundred and sixty-six consecutive coronary lesions in 95 consenting patients (mean age 59 +/- 11 years; 12 women) were randomly assigned to direct stenting (n = 88), or balloon predilatation followed by stenting (n = 78), using sirolimus- or paclitaxel-eluting stents. RESULTS: All procedures were uneventful. Crossover to balloon predilatation was necessary in 6 (7%) lesions randomized to direct stenting. During a 12-month follow up period, ischemia-driven angiography was performed in 13 patients. By intention to treat analysis, target lesion revascularization was required in 4 lesions, all of which were randomized to the predilatation group (p = 0.04). CONCLUSIONS: Direct stenting was feasible in up to 93% of attempted lesions. A strategy of direct stenting resulted in a significantly lower rate of target lesion revascularization over a 12-month follow-up period compared to balloon predilatation followed by stenting.

Sustained ventricular tachycardia induced by dobutamine stress echocardiography: a prospective study.

AIMS: To investigate the prognostic significance and electrophysiological characteristics of dobutamine stress echo (DSE)-induced sustained monomorphic ventricular tachycardia (VT). METHODS: In our department, 3022 DSE studies were carried out on 2688 patients, aged 54.7 +/- 11.8 years, over a 3.5 year period. Patients with DSE-induced VT were studied by means of coronary angiography and electrophysiological testing, and were followed-up for 17.8 +/- 9.3 months. RESULTS: During DSE, nine patients (0.3%) developed sustained monomorphic VT. Four patients had coronary artery disease, one developed spontaneous right coronary artery (RCA) dissection during DSE, one patient had peripartum cardiomyopathy and the remainder had normal coronary arteries. Logistic regression analysis did not identify clinical parameters such as left ventricular ejection fraction, documentation of an ischaemic response or the presence of non-viable myocardial segments during DSE, that could predict the occurrence of DSE-induced VT. Monomorphic VT was inducible by electrophysiological testing in two patients with CAD and reduced LVEF. During follow-up, only these two patients developed VT. CONCLUSION: Sustained monomorphic VT is a rare complication of DSE, with no predictive value for the identification of patients with coronary artery disease and no prognostic significance in patients with normal coronary arteries. No predictors of its occurrence were identified.

Transcoronary transplantation of autologous mesenchymal stem cells and endothelial progenitors into infarcted human myocardium.

The aim of the study was to investigate whether a combination of mesenchymal stem cells (MSCs) capable of differentiating into cardiac myocytes and endothelial progenitors (EPCs) that mainly promote neoangiogenesis might be able to facilitate tissue repair in myocardial scars. Previous studies have shown that intracoronary transplantation of autologous bone marrow stem cells results in improvement of contractility in infracted areas of human myocardium. Eleven patients with an anteroseptal myocardial infarction (MI) underwent transcoronary transplantation of bone marrow-derived MSCs and EPCs to the infarcted area through the left anterior descending artery. Eleven age- and sex-matched patients served as controls. Wall motion score index was significantly lower at follow-up in the transplantation (P = 0.04) but not in the control group. On stress echocardiography, there was improvement of myocardial contractility in one or more previously nonviable myocardial segments in 5 out of 11 patients (all with recent infarctions) and in none of the controls (P = 0.01). Restoration of uptake of Tc(99m) sestamibi in one or more previously nonviable myocardial scars was seen in 6 out of 11 patients subjected to transplantation and in none of the controls (P = 0.02). Cell transplantation was an independent predictor of improvement of nonviable tissue. Intracoronary transplantation of MSCs and EPCs is feasible, safe, and may contribute to regional regeneration of myocardial tissue early or late following MI.