Long-term effect of atrial fibrillation on the evolution of mitral and tricuspid valve regurgitation.

Objective: The present study aims to identify the long-term effects of atrial fibrillation (AF) on atrial remodelling and on the progression of mitral/tricuspid valve regurgitation (MR/TR).Methods: The severity of MR/TR was assessed by the colour jet area and by multi-integrative approach at baseline and after a period of 65 ± 10 months in 37 patients with permanent AF, in 80 patients with non-permanent AF (of whom 43 were treated with ablation) and in 53 control patients with sinus rhythm.Results: At baseline, AF patients had larger MR jet areas than control patients. At follow up, progression of MR, expressed as delta MR jet area, was 0.05 ± 1.3 cm2 in the control group, 0.73 ± 2.1 cm2 in the non-permanent AF group and 1.95 ± 3.6 cm2 in the permanent AF group (p = .001). Severe MR at follow up was observed in 0%, 2.5%, 8%, respectively. There was a significant positive correlation between progression of MR and increase of left atrium volume (r = 0.31, p < .001). After adjustment for baseline clinical and echocardiographic parameters, permanent AF remained independently associated with the progression of MR. Although rhythm control was better with AF ablation than with medical treatment only, the MR evolution was similar. Comparable findings, albeit less pronounced, were observed for the association between of AF and TR progression.Conclusions: The presence of longstanding AF is associated with a significant progression of MR/TR mainly due to atrial remodelling. Our data showed a beneficial effect of sustained rhythm control, either medically or by ablation, on MR/TR progression.

Impaired coronary flow reserve after a recent myocardial infarction: correlation with infarct size and extent of microvascular obstruction.

BACKGROUND: The exact relationship between the coronary flow reserve (CFR) and infarct size remains unknown. In this prospective study the relationship between the CFR both in the infarcted and remote myocardium and infarct size was investigated. Furthermore, the diagnostic value of the CFR to predict the extent of microvascular obstruction (MO) was evaluated. METHODS: In thirty patients the CFR was measured with a Doppler guide wire 6 ± 3 days after a first myocardial infarction (MI) in the infarct related and in a reference coronary artery. MO and infarct size were determined with magnetic resonance imaging. RESULTS: The CFR was inversely related to infarct size in the infarcted and remote myocardium (respectively, r=-0.60, p<0.01 and r=-0.62, p<0.01). In the infarcted myocardium the extent of MO was strongly related to the infarct size and was in a multivariate analysis the single significant determinant of the CFR and the hyperaemic flow. In the remote myocardium no relationship was present between infarct size and hyperaemic flow, but the baseline flow increased as the infarct size became larger (r=0.58, p<0.01). In a receiver operator characteristic (ROC) analysis, a CFR value ≤ 2 in the infarct related coronary artery offered the best sensitivity (65%) and specificity (71%) to detect the presence of MO (p<0.05). CONCLUSIONS: After MI, the CFR both in the infarcted and remote myocardium is inversely related to infarct size. In the infarcted myocardium, a CFR value ≤ 2 predicts the presence of MO with moderate sensitivity and specificity.

Coronary microvascular dysfunction after myocardial infarction: increased coronary zero flow pressure both in the infarcted and in the remote myocardium is mainly related to left ventricular filling pressure.

OBJECTIVE: To investigate the underlying mechanisms of a decreased coronary flow reserve after myocardial infarction (MI) by analysing the characteristics of the diastolic hyperaemic coronary pressure-flow relationship. DESIGN: Prospective study. SETTING: Tertiary care hospital. PATIENTS: 68 patients with a recent MI and 27 patients with stable angina pectoris (AP; control group). MAIN OUTCOME MEASURES: The intercept with the pressure axis (the zero flow pressure or Pzf) and slope index of the pressure-flow relationship (SIPF) were calculated from the simultaneously recorded hyperaemic intracoronary blood flow velocity and aortic pressure after successful coronary stenting. RESULTS: A stepwise increase in Pzf from AP (14.6 (8.0) mm Hg), over non-Q-wave MI (22.5 (9.1) mm Hg), to Q-wave MI (37.1 (12.9) mm Hg; p<0.001) was observed. Similar changes in Pzf were found in a reference artery perfusing the non-infarcted myocardium. Multivariate analysis showed that in both regions the left ventricular end-diastolic pressure (LVEDP) was the most important determinant of the Pzf. The SIPF was not statistically different in the treated vessel between patients with MI and AP, but was increased in MI patients with a markedly increased LVEDP. CONCLUSIONS: After an MI, the coronary pressure-flow relationship is shifted to the right both in the infarcted and in the non-infarcted remote myocardium, as shown by the increased Pzf. The correlation with Pzf suggests that elevated left ventricular filling pressures contribute to the impediment of myocardial perfusion in patients with infarction.

Mianserin and ventricular tachycardia: case report and review of the literature.

Mianserin is a drug frequently used to treat depression and sleep disturbances. Despite documented effects on various cardiac tissues in animal studies, mianserin has a very safe clinical profile. Only one case of ventricular arrhythmias in a patient treated with mianserin has been reported. This patient had a severe cardiac history. Our case is to our knowledge the first report on ventricular arrhythmias in a patient treated with mianserin without previous or present cardiac disease. After discontinuation of mianserin the arrhythmias disappeared within days. The literature on mianserin toxicity is reviewed.

Wide QRS complex tachycardia. Rapid method of prognostic evaluation.

UNLABELLED: A wide QRS complex tachycardia suggests a ventricular tachycardia (VT); but supraventricular tachycardia (SVT) is also possible. Some authors reported on the electrocardiographic signs for the differential diagnosis of VT and SVT with aberrancy. Frequently these signs are debatable and the diagnosis is uncertain. The purpose of the study was to evaluate the interest of a non-invasive study by transesophageal route for the evaluation of the nature of a wide QRS complex tachycardia in which a reliable ECG algorithm does not permit to distinguish VT from SVT with aberrancy. METHODS: Esophageal electrophysiologic study (EPS) was performed in 53 patients, aged from 16 to 85 years without bundle branch block (BBB) in sinus rhythm, but with wide-QRS tachycardia. The protocol consisted of atrial pacing at progressively higher rates and then programmed stimulation with one and two extrastimuli in control state and after isoproterenol infusion. Intracardiac EPS was performed in 49 of them. RESULTS: (1) Study was negative in nine patients; intracardiac EPS remained negative in four of them, induced a VT in five; (2) clinical tachycardia was induced in 44 patients: (a) in 29 of them, atrial pacing induced a BBB similar to aberrancy noted in tachycardia and the diagnosis of SVT with aberrancy was made; (b) in 15 patients, QRS complex remained narrow during atrial pacing; the diagnosis of VT was made in presence of AV dissociation and confirmed by intracardiac study. VT was induced by atrial or ventricular stimulation or was spontaneous during isoproterenol infusion. VT mechanism were bundle branch reentry [Am. J. Cardiol. 65 (1990) 322], verapamilsensitive VT [Am. J. Cardiol. 65 (1990) 322], catecholamine-sensitive VT [J. Cardiovasc. Electrophysiol. 7 (1996) 2]. Two patients had tachycardias of both natures either supraventricular or ventricular. CONCLUSION: Esophageal EPS was a safe, rapid and economic means to evaluate the mechanism of wide QRS tachycardia in 84% of patients; atrial pacing at progressively higher rates is very simple to reproduce the aberrancy of similar morphology in those patients who had wide-QRS tachycardia related to a SVT with aberrancy. If atrial pacing did not exactly reproduce the aberrancy in tachycardia, a VT should be suspected.

Correlation between electrogram morphology and standard criteria to validate bidirectional cavotricuspid block in common atrial flutter ablation.

AIM: Assessment of a bidirectional conduction block within the cavotricuspid isthmus (CTI) is critical during radiofrequency (RF) atrial flutter (AF) ablation. We investigated the use of bipolar atrial electrogram (BAE) morphology as an additional criterion identifying CTI block and tested it against two recognized criteria: differential pacing and reversal of the right atrial depolarization sequence during coronary sinus (CS) pacing. METHODS AND RESULTS: An RF ablation procedure was performed during 600 ms CS pacing in 100 consecutive patients with a common AF. BAE recorded along the CTI were continuously monitored. CTI conduction block was achieved by RF ablation in all patients and a clear change in BAE polarity in the Electrogram recorded by the dipoles located on the CTI and immediately lateral to the intended line of block (RS to QR pattern) associated with a confirmed CTI conduction block was observed in all cases. BAE morphology changes predicted bidirectional CTI conduction blocks with a 100% positive and a 100% negative predictive value. At a mean follow-up of 33 +/- 11 months, there was a 5% AF recurrence rate. CONCLUSIONS: Our study suggests that morphological changes in BAE recorded at sites lateral and adjacent to the target line of block may be used as a unique and robust criterion to validate CTI conduction block during AF ablation procedure.

Anti-glomerular basement membrane glomerulopathy in a young child.

We report the youngest patient with anti-glomerular basement membrane disease described in the literature to date. Age-dependent expression of the target antigen in this auto-immune disease explains the low incidence in young children. Despite adequate immunosuppression, renal function did not recover in our patient.