Double atrial potentials as a marker for isthmus block during ablation of atrial flutter

Assessment of success is an integral part in atrial flutter ablation. This work is concerned with evaluating the added value of recording double potentials along the ablation line induced to interrupt the macro-reentrant circuit of atrial flutter. Atrial flutter was ablated in 24 consecutive patients, 7 males and 7 females, their ages ranged from 10-65 years, with mean age of 37 +/- 12.5 years. The ablation was done through burning a continuous line across the cavo-tricuspid right atrial isthmus. In all patients pace-mapping indicated complete bidirectional isthmus block, we tried to record double potentials along the ablation line during pacing from the coronary sinus ostium. The patients were followed up for 6 months, recurrent cases were reablated. the acute success rate was 100% in both the initial and the second procedures. Nine recurrences [37.5%] occurred during the period of follow up, which were reablated; none of the reablated cases had any recurrence during six months of follow up, with overall late recurrences of nine patients out of 33 procedures [27%]. Whenever double atrial potentials were recorded along the ablation lines, there was no recurrence [specificity of 100%], but in cases in which these potentials were not recorded, it did not predict recurrence except in 40% of cases [sensitivity 60%]. Predictors of late recurrence, in this study, were age of the patient and Duration of symptoms. We compared between 4 and 8 mm tip ablation catheters, it turned to be that the recurrence and the procedure duration was lower with the use of 8 mm tip catheters. Patient with structural heart disease in this study were older, with more duration of symptoms and their procedures were longer. In conclusion, there was an added value of recording double atrial potentials to the conventional mapping technique used to identify bidirectional isthmus block in patients with atrial flutter. In addition, 8 mm tip catheters were considered safe and effective in the term of reducing the time of the procedure and recurrence rate specially when combined with SVC approach. Abbreviations: SVC: superior vena cava

Detection of significant left coronary artery stenosis by reduced transthoracic coronary sinus flow reserve

Currently available methods for measurement of coronary flow reserve are invasive, time consuming and need laboratory equipment and staff. So, the aim of this study was to demonstrate coronary sinus flow by transthoracic echocardiography and to determine the feasibility of using CSFR for the diagnosis of left coronary artery stenosis. This study comprised two groups; patients group which consisted of 30 patients with angiographically proven isolated LCA stenosis, and control group which consisted of 10 healthy volunteers. All patients and subjects were examined by echo Doppler to measure coronary sinus diameter and coronary sinus flow dynamics at baseline and again at peak dipyridamole infusion. CSFR was measured by both peak and volumetric methods. At baseline, the coronary sinus diameter and Doppler parameters showed insignificant difference between both groups [P> 0.05]. At peak dipyridamole, a significant increase in CS diameter was seen in both groups [P< 0.01] without significant difference in between [P > 0.05]. However, dipyridamole induced increase of velocity and volume characteristic of CS was marked in control group than in patients group [P< 0.001]. CSFRp and CSFRv showed a highly significant decrease in patients group than control group [P<0.001]. CSFR by peak or volumetric methods

Percutaneous valvuloplasty for isolated pulmonary valve stenosis: 3 years follow-up

To determine the results of pulmonary balloon valvuloplasty immediately after the procedure and six months during the follow up period, 25 patients [8 males and 17 females] were studied by two- dimensional echocardiography combined with pulsed and continuous Doppler echocardiography before and after dilatation for three successive years. All patients underwent clinical examination, resting electrocardiography [ECG] and chest X-ray before, after dilatation and during the follow up period. The average pressure gradient across pulmonary valve was 82.64 +/- 50.61 mmHg before dilatation that reduced immediately after dilatation to 17.08 +/- 0.51 mmHg, after one year follow up to 18.8 +/- 12.59 mmHg and after three years follow up to 20.48 +/- 13.84 mmHg. The average cardiac output was 3.18 liter before dilatation that increased to 5.78 liter immediately after dilation [by thermo dilution technique]. ECG showed criteria of right ventricular hypertrophy in all patients predilatation which disappeared in 19 patients and decreased in the rest of the patients. All patients had lung oligemia, eight had post stenotic dilatation and all had right ventricular enlargement in the postero-anterior and the left lateral view of chest X-ray. Lung oligemia disappeared in all patients