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Carlos Aguiar

Publications and source records attributed to Carlos Aguiar.

At least 19 recordsLinked to original sources
PubMed2006

Subacute left ventricle free wall rupture after acute myocardial infarction: awareness of the clinical signs and early use of echocardiography may be life-saving.

Left ventricular free wall rupture (LVFWR) is a fearful complication of acute myocardial infarction in which a swift diagnosis and emergency surgery can be crucial for successful treatment. Because a significant number of cases occur subacutely, clinicians should be aware of the risk factors, clinical features and diagnostic criteria of this complication. We report the case of a 69 year-old man in whom a subacute left ventricular free wall rupture (LVFWR) was diagnosed 7 days after an inferior myocardial infarction with late reperfusion therapy. An asymptomatic 3 to 5 mm saddle-shaped ST-segment elevation in anterior and lateral leads, detected on a routine ECG, led to an urgent bedside echocardiogram which showed basal inferior-wall akinesis, a small echodense pericardial effusion and a canalicular tract from endo to pericardium, along the interface between the necrotic and normal contracting myocardium, trough which power-Doppler examination suggested blood crossing the myocardial wall. A cardiac MRI further reinforced the possibility of contained LVFWR and a surgical procedure was undertaken, confirming the diagnosis and allowing the successful repair of the myocardial tear. This case illustrates that subacute LVFWR provides an opportunity for intervention. Recognition of the diversity of presentation and prompt use of echocardiography may be life-saving.

Aged↗
PubMed2006

Metabolic score--a simple risk marker in non-ST elevation acute coronary syndromes.

BACKGROUND: Atherothrombotic coronary artery disease is increasingly recognized as part of a systemic metabolic disorder. However, little is known about the significance of metabolic dysfunction in the setting of acute coronary syndrome. OBJECTIVE: Our aim was to assess the prognostic implications of markers of metabolic dysfunction at hospital admission obesity (BMI > 30), previous history of hypertension, admission glucose > 128 mg/dl, triglycerides > 150 mg/dl, and HDL cholesterol < 40 mg/dl for men, or < 50 mg for women--in patients with non-ST elevation acute coronary syndromes (ACS). METHODS: A total of 303 consecutive patients admitted to the CCU with ACS were included in the study. Mean age was 63 +/- 10 years, and 86% were male. The primary end-point was a composite of death or non-fatal acute myocardial infarction (MI) at one-year follow-up. Each marker was assigned one point, and a metabolic score (MetScore) was calculated for each individual patient by adding together the number of markers present at hospital admission. Three groups were considered: group 1 (MetScore 0) with 0 markers (n = 30); group 2 (MetScore 1 to 3) with 1 to 3 markers (n = 222); and group 3 (MetScore 4 to 5) with 4 to 5 markers (n = 51). RESULTS: The cumulative incidence of death or MI was 14.5%. We found a statistically significant relation between MetScore and outcome at one-year follow-up. The event rate was 3.3% in the MetScore 0 group, 13.9% in the MetScore 1 to 3 group and 23.5% in the MetScore 4 to 5 group (p = 0.0114). MetScore was an independent predictor of death or MI at one year, with a 2.3-fold risk increase (95% CI: 1.32-4.01; p = 0.003) from one group to the next. Other variables identified as independent predictors of outcome were advanced age, Killip class, ST-segment depression and previous CABG. The incidence of the primary end-point in diabetic patients without significant metabolic dysfunction and non-diabetic patients with SMD was similar (21.2% vs. 22.7%; p = NS). CONCLUSION: Assessment of markers of metabolic dysfunction on admission in patients with non-ST elevation acute coronary syndromes, adds important prognostic information to conventional clinical, ECG and risk stratification markers and could prove useful in establishing secondary prevention strategies.

Acute Disease↗
PubMed2005

TIMI, PURSUIT, and GRACE risk scores: sustained prognostic value and interaction with revascularization in NSTE-ACS.

AIMS: Regarding prognosis, patients with a non-ST elevation acute coronary syndrome (ACS) are a very heterogeneous population, with varying risks of early and long-term adverse events. Early risk stratification at admission seems to be essential for a tailored therapeutic strategy. We sought to compare the prognostic value of three ACS risk scores (RSs) and their ability to predict benefit from myocardial revascularization performed during initial hospitalization. METHODS AND RESULTS: We studied 460 consecutive patients admitted to our coronary care unit with an ACS [age: 63+/-11 years, 21.5% female, 55% with myocardial infarction (MI)]. For each patient, the Thrombolysis In Myocardial Infarction (TIMI), Platelet glycoprotein IIb/IIIa in Unstable agina: Receptor Suppression Using Integrilin (PURSUIT), and Global Registry of Acute Coronary Events (GRACE) RSs were calculated using specific variables collected at admission. Their prognostic value was evaluated by the combined endpoint of death or MI at 1 year. The best cut-off value for each RS, calculated with receiver operating characteristic curves, was used to assess the impact of myocardial revascularization on the combined incidence of death or MI. Death or MI at 1 year was 15.4% (32 deaths/49 MIs). The best predictive accuracy for death or MI at 1 year was obtained by the GRACE RS (AUC) [area under the curve: 0.715; confidence interval (CI: 0.672-0.756)] but the performance of the PURSUIT RS (AUC: 0.630; CI: 0.584-0.674), and TIMI RS (AUC: 0.585; CI: 0.539-0.631) was also good. We found a statistically significant interaction between the risk stratified by the best cut-off value for the GRACE and PURSUIT RSs and myocardial revascularization, with a better prognosis for the high-risk patients. The high-risk patients represented 36.7, 28.7, and 57.8% of the population, for the GRACE, PURSUIT, and TIMI RSs, respectively. CONCLUSION: The RSs studied demonstrated a good predictive accuracy for death or MI at 1 year and enabled the identification of high-risk subsets of patients who will benefit most from myocardial revascularization performed during initial hospital stay.

Adult↗
PubMed2005

Cholesterol pericarditis--relapsing pericardial effusion in a patient with rheumatoid arthritis.

Cholesterol pericarditis is an uncommon form of pericardial disease, of unknown pathophysiology, that is characterized by chronic relapsing, usually large, pericardial effusions that are distinctive due to a high level of cholesterol. Usually it is idiopathic, but it can be associated with various systemic diseases such as hypothyroidism, rheumatoid arthritis and tuberculosis, among others. Its clinical course is usually indolent and complications such as cardiac tamponade and chronic constrictive pericarditis are relatively rare. However, the need for surgery for complete treatment has been reported in at least 10 % of cases. When rheumatoid arthritis is the underlying cause, this outcome is more frequent among those with an acute episode of pericarditis during the course of the disease. We report the case of a 61-year-old female rheumatoid arthritis patient, who presented with heart failure due to a large pericardial effusion and was successfully treated by a surgical approach.

Arthritis, Rheumatoid↗
PubMed2005

Prognosis of non-ST-segment elevation acute coronary syndrome in patients with prior percutaneous coronary intervention.

BACKGROUND: There is disagreement concerning the prognostic value of a prior history of percutaneous coronary intervention (PCI) in patients with non-ST-segment elevation acute coronary syndromes (ACS). This study characterizes these patients and investigates the impact of prior PCI on their prognosis. METHODS: 448 consecutive patients admitted due to ACS between 1998 and 2000 were evaluated. Patients with prior PCI were compared to the others with regard to baseline demographic and clinical features. The study endpoint was death or myocardial infarction at one-year follow-up. The impact of prior PCI on the outcome was analyzed. In patients with prior PCI, the prognostic value of the time interval between PCI and current admission was assessed. In those patients who underwent coronary angiography during the index hospitalization, the culprit lesion features were evaluated. RESULTS: 134 patients (30%) with prior PCI were identified. Overall ACS patients had an event rate of 19% at one year. A history of prior PCI was not an independent predictor of outcome, but in the 44 patients with PCI performed during the 117 days before the index hospitalization, the event rate was significantly higher (30% versus 13%). Prior PCI in the previous 117 days was an independent risk predictor (adjusted OR 4.81; 95% CI, 1.57-14.71; p = 0.006). In these patients restenosis was the most frequent culprit lesion (60% versus 30%; p = 0.003). CONCLUSIONS: In ACS patients, a history of PCI in the previous four months is an independent predictor of adverse outcome at one-year follow-up.

Adult↗
PubMed2004

Ventral cardiac denervation reduces the incidence of atrial fibrillation after coronary artery bypass grafting.

OBJECTIVES: Because the autonomic nervous system is an important determinant in the appearance of atrial fibrillation, we have assessed the role of ventral cardiac denervation for its prevention. METHODS: Patients undergoing low-risk coronary artery surgery were enrolled. No routine antiarrhythmic drugs were administered before or after the operation. Ventral cardiac denervation was performed in 207 patients, and 219 patients were used as control subjects. Denervation was performed before cardiopulmonary bypass. The groups were comparable regarding demographic, clinical, and operative variables. RESULTS: The additional time for the denervation was 5 +/- 2 minutes, and there were no associated complications. Postoperative atrial fibrillation was present in 15 (7%) patients undergoing ventral cardiac denervation (95% confidence interval, 4%-12%) and in 56 (27%) control subjects (95% confidence interval, 18%-35%). Patients submitted to ventral cardiac denervation had fewer and less severe episodes of atrial fibrillation, and no patient had atrial fibrillation after discharge. Ventral cardiac denervation was the most significant predictor of postoperative atrial fibrillation (odds ratio, 0.42; confidence interval, 0.23-0.78; P =.006). Age of greater than 65 years (odds ratio, 1.67; confidence interval, 0.96-2.9; P =.067) was a highly suggestive predictor. The analysis of the effect of ventral cardiac denervation correlated with the patient's age showed a more pronounced effect in patients younger than 70 years (odds ratio, 0.43; confidence interval, 0.22-0.86; P =.022) CONCLUSIONS: Ventral cardiac denervation is a fast and low-risk procedure. Its use significantly reduces the incidence and severity of atrial fibrillation after routine coronary artery bypass surgery. Patients younger than 70 years of age are expected to have a higher success rate than those older than 70 years.

Adrenergic beta-Antagonists↗
PubMed2004

Atrial flutter ablation: correlation between isthmic activation times and flutter cycle.

BACKGROUND: Ablation of typical atrial flutter relies on the suppression of electrical conduction along the cavo-tricuspid isthmus. Bidirectional isthmus block is a criterion of successful ablation and is associated with the presence of different activation times on each side of the ablation line. OBJECTIVE: The aim of this study was to determine whether the difference in isthmic activation times correlates with the length of the atrial flutter cycle. POPULATION AND METHODS: We studied 31 patients with typical atrial flutter (93.6% male, mean age 66 +/- 9 years) who underwent successful ablation during tachycardia. CARTO electroanatomic mapping was used to confirm diagnosis of isthmus-dependent atrial flutter, guide the ablation line creation and assess its efficacy. At the end of the procedure, a three-dimensional activation map of the right atrium was constructed, under pacing from the coronary sinus ostium (with a 500 ms cycle). Activation times on the lateral (right) and septal (left) sides of the ablation line were measured. The difference between these two activation times was termed the difference in isthmic activation times (delta IAT), and was compared to the flutter cycle length. RESULTS: Mean activation times were 173.7 +/- 34.3 ms on the lateral border of the ablation line and 19.1 +/- 12.5 ms on the septal border. Mean delta IAT was 154.6 +/- 27.8 ms and mean atrial flutter cycle length was 257.5 +/- 30.6 ms. delta IAT and flutter cycle length were significantly correlated (r = 0.503, p = 0.0039). The linear regression equation that best described this result was: delta IAT = 37 + (0.46 x flutter cycle). CONCLUSION: After atrial flutter ablation, a difference in isthmic activation times of more than half the flutter cycle length was associated with isthmus conduction block.

Aged↗
PubMed2003

Revascularization and prognosis in female patients with non-ST-segment elevation acute coronary syndromes.

BACKGROUND: After an acute myocardial infarction, women have a higher risk of death or reinfarction. In unstable angina, female gender seems to be protective. On the other hand, studies suggest that women are less frequently given coronary angiography. OBJECTIVES: To evaluate, in our population of patients admitted for non-ST-elevation acute coronary syndrome (ACS), the influence of gender in prognosis and in the use of invasive procedures. POPULATION AND METHODS: We studied 387 consecutive patients, 20% female, admitted to our ICU for non-ST-segment elevation ACS. We compared demographic and clinical variables, the use of coronary angiography and myocardial revascularization procedures, according to gender. We analyzed the combined endpoint of death or (re)infarction at 30 days and for the total follow-up period of 420 +/- 322 days. RESULTS: The women were older (65 +/- 10 vs. 62 +/- 11 years, p = 0.05), and more frequently had a history of hypertension (p = 0.005), diabetes mellitus (p = 0.07), previous surgical myocardial revascularization (p = 0.048) and higher heart rate on admission (p = 0.048). Smoking was more frequent in men (p < 0.001). The most frequent diagnosis was unstable angina; 76% for women vs. 66% in men (p = 0.12). Coronary angiography was performed during hospitalization in 87%, in both genders. Myocardial revascularization was performed in 62% of the women and 69% of the men (p = 0.26). At 30 days, the frequency of death or (re)infarction was 11% for women and 10% for men (log-rank, p = 0.79). By multivariate analysis (Cox regression), the independent predictors of outcome at 30 days were previous myocardial revascularization and heart failure on admission. For the total follow-up, we did not find differences in the occurrence of the combined endpoint, and the independent predictors of outcome were previous surgical myocardial revascularization, heart failure on admission, ST segment depression on the admission ECG and surgical myocardial revascularization. CONCLUSIONS: In non-ST-elevation ACS, women present some differences in their demographic and clinical profile. We did not find differences in the use of invasive procedures or prognosis in the short and medium term.

Aged↗
PubMed2003

Identification of pulmonary vein foci by non-contact mapping in patients with paroxysmal atrial fibrillation.

AIMS: Ectopies from the pulmonary veins may cause paroxysmal atrial fibrillation and their discrete ablation may be curative. In the absence of focal activity during the procedure, identification of target sites with conventional techniques is difficult. We investigated the feasibility of non-contact mapping (EnSite) for identification and successful ablation of pulmonary vein foci in such cases. METHODS AND RESULTS: We studied 7 patients with idiopathic paroxysmal atrial fibrillation referred for percutaneous ablation and not presenting spontaneous or inducible atrial premature beats during the procedure. An EnSite balloon catheter and an ablation catheter (NaviStar) were placed inside the left atrium. The ablation catheter was also used for electroanatomic mapping (CARTO) of specific sites. Multiphasic pulmonary vein potentials were detected on virtual electrograms and tagged on the non-contact map and confirmed with conventional mapping. The procedural endpoint was elimination or dissociation of the multiphasic potential. Non-contact mapping identified 13 foci of multiphasic potentials in the seven patients (5 foci were initially identified by EnSite), and discrete ablation suppressed 9 of them (69%). Six months later, 4 of the 5 patients in whom all foci were suppressed remain asymptomatic, in sinus rhythm, under no medication. CONCLUSION: In patients with paroxysmal atrial fibrillation and no ectopic activity during electrophysiological study virtual electrograms may complement conventional techniques in detecting hidden pulmonary vein foci and may be used to evaluate ablation efficacy.

Aged↗
PubMed2003

Serologic markers for cytomegalovirus in acute coronary syndromes.

BACKGROUND: Several studies relate cytomegalovirus (CMV) infection to the development of atherosclerosis. Its influence in triggering acute coronary syndromes (ACS) is not known. OBJECTIVES: We set out to identify a relationship between CMV infection, occurrence of ACS and prognosis. METHODS: Serologic markers (IgM and IgG) for CMV were tested prospectively at admission and at 30 days, in patients (pts) admitted to our CCU for ACS. Serologic markers for CMV were also tested in a group of pts with stable coronary artery disease admitted for elective coronary angiography. A greater than two-fold elevation of IgG titer at 30 days was defined as reactivation/reinfection. At 30 days and six months, the composite endpoint of death, myocardial (re)infarction and re-admission for unstable angina was evaluated. RESULTS: There were 60 pts with ACS in the study group (age 63 +/- 10 years, 75% male) and 31 pts in the control group (age 64 +/- 10 years, 71% male). On admission, 95% of the pts with ACS and 81% in the control group presented a positive IgG (p = 0.029). In the study group, at 30 days, the only pt with a 3-fold titer elevation had an endpoint. The percentage was 17% for the group with a > or = 2- and < 3-fold elevation and 11% in the group without reactivation (p = 0.034). At six months, 50% of the patients with a greater than 2-fold titer elevation and 15% of the remaining patients had an endpoint (p = 0.017). In the control group, at 30 days, 3 pts (10%) had a significant elevation in IgG titer, > or = 2- and < 3-fold, without endpoint. CONCLUSIONS: In pts with ACS, we found a higher prevalence of serologic markers for CMV than in pts with stable coronary disease. An elevation in IgG titer for CMV was associated with a worse outcome at 30 days and six months.

Adult↗
PubMed2003

Ablation of atrial fibrillation in mitral valve disease patients: five year follow-up after percutaneous pulmonary vein isolation and mitral balloon valvuloplasty.

BACKGROUND: The association between atrial fibrillation (AF) and mitral valve disease is frequent. Isolation of the pulmonary veins by radiofrequency energy applications performed intraoperatively has been proposed for patients with AF in whom mitral valve surgery has been indicated. Balloon mitral valvuloplasty is currently the preferred procedure for patients with mitral stenosis and a favorable valve anatomy. AIM: To evaluate the short- and long-term results of percutaneous pulmonary vein isolation for the treatment of AF in patients with mitral stenosis undergoing balloon mitral valvuloplasty. METHODS: Five patients (four male and one female, age 43 +/- 4 years) underwent balloon mitral valvuloplasty concomitant with pulmonary vein isolation between August 1996 and February 1997. These patients had permanent AF, diagnosed 31 +/- 12 months previously; their mitral valve area was 1.0 +/- 0.25 cm2 and their left atria measured 54 +/- 5 mm. Balloon mitral valvuloplasty was performed via a transseptal approach, and then four ablation lines were created in the left atrial posterior wall to encircle all four pulmonary veins. Radiofrequency applications lasted 45 seconds each, and aimed at a maximum preset temperature of 65 degrees C. Electrical cardioversion was performed at the end of the procedure. RESULTS: Mitral valve area increased 1.0 +/- 0.3 cm2 after valvuloplasty. The number of radiofrequency applications per patient was 37 +/- 3, and the average duration of the entire treatment was 131 +/- 28 minutes. Fluoroscopy time averaged 32 +/- 12 minutes. All patients were discharged in sinus rhythm, and mitral flow Doppler evaluation at one month showed a biphasic pattern in all cases, with the A wave measuring 70 +/- 15 cm/sec. Three patients maintained sinus rhythm at five-year follow-up. Of these patients, one had developed a left atrial flutter at four-year follow-up and underwent ablation. The remaining two patients presented AF at five year follow-up. CONCLUSIONS: Percutaneous isolation of the pulmonary veins concomitant with balloon mitral valvuloplasty had suppressed AF in 60% of patients by five-year follow-up.

Adult↗
PubMed2003

Percutaneous ablation of atrial fibrillation: assessment of outcomes at 1-year follow-up.

OBJECTIVE: Current non-pharmacologic treatment strategies for atrial fibrillation (AF) involve discrete ablation of ectopic foci or isolation of the pulmonary vein (PV) ostia, which have been implicated in the genesis of this rhythm disorder. The aim of this study was to determine intermediate and long-term outcomes after percutaneous AF ablation and predictors of successful treatment. POPULATION AND METHODS: We studied 29 consecutive patients (72% male, mean age 52.3 +/- 13 years) who underwent percutaneous ablation of AF refractory to antiarrhythmic drug therapy. AF was idiopathic in 22 patients and the remaining 7 patients were hypertensive. Six patients had permanent AF and the others had recurrent paroxysmal AF (with at least 1 episode a week). Left atrial size was 40.3 +/- 6.1 mm. A total of 35 ablation procedures were performed, 12 using the focal ablation technique and 23 by PV isolation. Six patients underwent a redo procedure. Patients were evaluated at 1-year follow-up (symptoms, medication, ECG and Holter monitoring). Predictors of successful treatment were identified among baseline clinical variables (age, gender, hypertension), LA size, AF sub-type, ablation technique, and number of isolated PV, using multivariable logistic regression. RESULTS: At 1-year follow-up, 20 patients presented sinus rhythm (69%), of whom 7 were taking antiarrhythmic drugs and remained free of AF relapse. Out of the total of 35 procedures, 2 immediate complications occurred: pericardial tamponade in one patient and right phrenic nerve palsy in another. Predictors of long-term success were absence of a prior history of hypertension and isolation of at least three PV (p = 0.01 for both independent predictors). CONCLUSION: Two out of three patients who underwent AF ablation presented sinus rhythm one year after the intervention. Isolation of at least three PV and idiopathic etiology are independent predictors of successful treatment.

Atrial Fibrillation↗
PubMed2002

Prognostic value of continuous ST-segment monitoring in patients with non-ST-segment elevation acute coronary syndromes.

BACKGROUND: Patients with non-ST-segment elevation acute coronary syndromes constitute a heterogeneous group concerning prognosis. The 12-lead ECG at rest is recommended for early risk stratification but is unable to reflect the dynamic nature of myocardial ischemia and coronary thrombosis. This study investigated whether continuous ST-segment monitoring provides early prognostic information in such patients. METHODS: We prospectively studied 183 patients admitted due to chest pain at rest suggestive of an acute coronary syndrome. ST-segment monitoring was performed continuously for 24 hours from admission. Cardiac-specific troponin I levels were determined on admission and every 6 hours for the first 24 hours. The endpoint was defined as death or nonfatal myocardial infarction, whichever occurred first by 30 days follow-up. RESULTS: ST episodes, defined as transient ST deviations of at least 0.1 mV, were detected in 50 patients (27.3%) and associated with worse 30-day outcome: 22.0% endpoint rate compared to 6.8% for patients without ST episodes (P = 0.003). In a multivariate analysis, the presence of ST episodes (hazard ratio, 3.07; 95% CI, 1.26 to 7.46; P = 0.014) and peak troponin I levels > 0.2 microg/L (hazard ratio, 2.65; 95% CI, 1.01 to 6.95; P = 0.048) were independent predictors of prognosis. The combination of ST-segment monitoring and peak troponin I identified patients at low (2.5%, n = 79), intermediate (14.5%, n = 76), and high (25.0%, n = 28) risk for the 30-day endpoint. CONCLUSIONS: In patients with non-ST-segment elevation acute coronary syndromes, continuous ST-segment monitoring provides on-line early prognostic information, in addition to troponin I levels.

Aged↗
PubMed2002

Influence of prior medication on mode of presentation and prognosis of acute coronary syndromes.

OBJECTIVES: To evaluate the influence of prior medication on mode of presentation and short-term prognosis of acute coronary syndromes (ACS). DESIGN: Prospective study. SETTING: Coronary intensive care unit in Santa Cruz Hospital. POPULATION: We included 425 consecutive patients admitted for ACS. METHODS: Prior medication with anti-platelet agents, beta-blockers, nitrates, calcium channel blockers, statins and angiotensin-converting enzyme (ACE) inhibitors was recorded on admission. Medication introduced in the last 7 days was excluded. Using a multivariate analysis model we examined the impact of baseline characteristics and previous medication on mode of presentation of ACS. We also evaluated their influence on short-term prognosis (death or non-fatal myocardial (re)infarction in the first 30 days). RESULTS: Of the 425 patients studied 228 (53.6%) presented with unstable angina (UA), the remainder with acute myocardial infarction (AMI) (24.7% with ST elevation). Medication prior to admission included anti-platelet agents in 53.7% of patients, beta-blockers in 44.2%, nitrates in 48.2%, calcium channel blockers in 36.9%, statins in 28.9% and ACE inhibitors in 38.6%. During the first 30 days, 14 deaths (3.3%) and 37 (re)infarctions (8.7%) occurred. The combined occurrence of death or (re)infarction was 10.8%. Variables with significant and independent influence on mode of presentation of ACS were male gender, presence of known coronary artery disease and previous medication with anti-platelet agents and beta-blockers. Male gender was a predictor of AMI as mode of presentation, whereas a previous history of coronary artery disease and medication with anti-platelet agents or beta-blockers predicted UA. Short-term prognosis was influenced by heart failure symptoms on admission, but not by previous medication. CONCLUSION: Previous medication with anti-platelet agents and beta-blockers was associated with an increased frequency of UA as mode of presentation of ACS. No relation between previous medication and short-term prognosis was observed in the present study.

Adrenergic beta-Antagonists↗
PubMed2002

Electronanatomical mapping and ablation of atrial tachycardias with the CARTO system.

UNLABELLED: Variable success rates in the ablation of atrial tachycardias using conventional electrophysiology have been achieved. There is no precise relation between P wave morphology in surface ECG and atrial electrophysiology, and this fact makes it more difficult to locate ectopic atrial foci. The CARTO system creates atrial activation maps that relate an anatomical location to an electrical potential. The aim of this study was to evaluate the efficacy of CARTO guided radiofrequency (RF) ablation of atrial foci. The population consisted of 10 consecutive patients with atrial tachycardia resistant to more than 2 drugs, 7 female, mean age 45 +/- 12 years. CARTO activation maps were constructed based on atrial tachycardia or premature beats. Radiofrequency energy was applied to the earliest activation zone. Immediate success was defined as suppression of ectopic atrial activity. Ectopic foci were located on the ostium of the coronary sinus (3 patients), crista terminalis (1 patient), right atrial appendage (1 patient), interatrial septum (1 patient) and in the pulmonary veins (4 patients). The activation maps contained 85 +/- 35 points. The number of RF applications ranged from 1 to 11 (mean 4). Immediate and 6 month success rate was 90%. We were not able to treat one patient with a focus in the right atrial appendage. No attempt was made to limit procedure or fluoroscopy time in our study. Nonetheless all procedures lasted less than 150 min, and fluoroscopy times were less than 30 minutes. CONCLUSIONS: The CARTO system precisely located ectopic atrial foci, allowing a high success rate in the ablation of focal atrial tachycardias.

Adult↗
PubMed2002

Atrial fibrillation and effective refractory period of the pulmonary vein ostia.

BACKGROUND: The pathogenesis of atrial fibrillation (AF) is not completely understood. The role of pulmonary veins (PV) in AF initiation is documented, and the recent demonstration of persistent fibrillatory activity in an isolated PV suggests that the PV play a role in the maintenance of AF. OBJECTIVE: Since AF is facilitated by multiple reentry circuits in atrial tissue with short effective refractory periods (ERP) and prolonged conduction times, we investigated whether PV have shorter ERP compared with the left atrium (LA). POPULATION AND METHODS: The study population consisted of five male patients, between 45 and 78 years of age, with normal sized LA; three had coronary artery bypass surgery (and no previous history of atrial arrhythmias) and two had paroxysmal lone AF refractory to antiarrhythmic drugs and were referred for percutaneous ablation with radiofrequency energy. In the surgical patients, epicardial bipolar pacing wires were inserted in the PV ostia and LA roof at the end of the procedure. Post-operatively, the pacing wires were used to determine atrial thresholds and ERP in the PV ostia and LA roof. In the AF patients, atrial thresholds and ERP at these locations were obtained with the mapping/ablation catheter before and after PV isolation. ERP were determined with a basic pacing cycle length of 500 ms and a single extrastimulus with an initial coupling interval of 350 ms, gradually decreased (10 ms at a time) until atrial capture failure or AF induction. RESULTS: ERP in the LA roof were longer than 210 ms. The shortest ERP was always obtained in a PV ostium, with the shortest in the left PV ostia. The ERP values of the right inferior PV most resembled those of the LA roof. In patients referred for ablation, AF was induced when PV ostia with ERP shorter than 200 ms were stimulated. CONCLUSION: In the present study, the ERP of PV ostia were shorter than LA ERP, possibly explaining not only the presence of ectopic foci in the PV ostia, but also sustained fibrillatory activity in isolated PV, despite conversion of the atria to sinus rhythm. This fact may also explain the higher success rate and the preference for PV isolation in AF ablation.

Aged↗