Biomedical subjects

Petros S Dardas

Publications and source records attributed to Petros S Dardas.

6 recordsLinked to original sources

PubMed2004

Left atrial volumes, function and work before and after mitral valve repair in chronic mitral regurgitation.

BACKGROUND AND AIM OF THE STUDY: Despite the effect of mitral valve repair in left ventricular (LV) function having been extensively studied, investigations of left atrial (LA) performance indices are minimal. This prospective study was undertaken to analyze LA volumes, function and work in patients with chronic mitral valve regurgitation (MR) who underwent mitral valve repair; the analyses were conducted both before and six months after surgery. METHODS: Twenty patients (15 males, five females; mean age 51.4 +/- 12.5 years) with severe MR (grade IV) due to floppy mitral valve/mitral valve prolapse (FMV/MVP; anterior, posterior or both) underwent mitral valve repair. LA volumes, maximal at mitral valve opening (LAmax); minimal at valve closure (LAmin); and at onset of atrial systole (P-wave on ECG, LAP); and transmitral Doppler A-wave velocity were measured before and six months after surgery. LA stroke volume (LASV) = LAP - LAmin; LA ejection fraction (LAEF) = LASV/LAP; LA kinetic energy (LAKE) = 1/2 x LASV x 1.06 (specific gravity of blood) x A2 (dyne x cm x 10(3)); LA and LV dimensions and functions were assessed at the same time. RESULTS: NYHA functional class was improved postoperatively by at least one grade. LV systolic and diastolic dimensions were reduced significantly in all patients (p <0.001). LA volumes (LAmax, LAmin and LAP) were decreased significantly in all patients (p <0.001); LASV remained unchanged. LAEF and LAKE were increased significantly (both p <0.001). The A-wave was also increased (p <0.001). CONCLUSION: Increased LA work (LAKE) after mitral valve repair, despite a decrease in LA volumes, suggests that LA muscle dysfunction was present before surgery. LA involvement may precede LV involvement. The determination of LA performance and work will help to optimize the timing of surgery in patients with FMV/MVP and MVR.

Adult↗

PubMed2003

A technique for type 4a coronary bifurcation lesions: initial results and 6-month clinical evaluation.

In routine practice, lesions in coronary bifurcations are frequent. This relatively high frequency may be underestimated due to the presence of false bifurcation lesions (lesions of the main branch without significant lesion of the sidebranch), which may become true bifurcation lesions after stenting due to axial plaque redistribution. In this report, we describe our initial experience with a new technique for the treatment of type 4a bifurcation lesions (main branch ostial lesion stenosis of the main vessel immediately after the bifurcation, not involving the sidebranch) using a new technique for primary stenting of the main vessel with simultaneous kissing balloon of the sidebranch in an effort to avoid the snowplough effect.

Aspirin↗

PubMedDate not supplied

Medium-term results from the clinical and angiographic follow-up of patients after angioplasty and implantation of sirolimus-eluting stents.

INTRODUCTION: The aim of this study was to evaluate the medium-term clinical and angiographic results, as well as the occurrence and treatment of restenosis, following the implantation of sirolimus-eluting stents (SES) in patients undergoing coronary angioplasty. METHODS: All patients who have an SES implanted in our department are entered into a database, with a view to evaluating the use of such stents in everyday clinical practice. This study included patients who consented to repeat angiography 8+/-2.4 months after stent implantation. The study population consisted of 91 patients (63 men, mean age 58+/-8.1 years) with 116 stenoses in all. This represented 17.4% of all patients who had an SES implanted during the study period. All the angiographic examinations were analysed independently using quantitative coronary analysis in order to determine the relationship between clinical and angiographic data and restenosis and late lumen loss. RESULTS: The mean vessel diameter was 2.5+/-0.48 mm and the mean lesion length was 12.61+/-1.54 mm. The late lumen loss was 0.04+/-0.49 mm. Restenosis was seen in 10 patients (12 vessels), of whom 4 were diabetics. The restenosis was in-stent in 7 vessels, in-segment in 5, and was localised (length of restenosis <10 mm) in all patients. After repeat angioplasty and SES implantation all the patients with restenosis remained free of symptoms 8+/-1.5 months later. Diabetes mellitus was the only factor to be correlated with restenosis. CONCLUSIONS: Restenosis following implantation of SES is mainly localised and occurs with about the same frequency within and outside the stent. The incidence of major cardiac events and restenosis following SES implantation is low. However, their long term efficacy in everyday clinical practice must be proved in large randomised studies in order to confirm the results presented here.

Aged↗

PubMedDate not supplied

Papillary fibroelastoma of the cardiac valves: a rare cause of embolic stroke.

Papillary fibroelastomas are rare, primary, benign cardiac tumours most frequently located in the heart valves. They are a potential cause of systemic emboli, stroke, myocardial infarction and sudden death. We present two cases of papillary fibroelastomas located in the mitral and aortic valves of patients who had suffered multiple strokes. The fibroelastomas were diagnosed using transoesophageal echocardiography and the patients were treated surgically, with broad excision of the tumours and preservation of the valves. The echocardiographic and microscopic characteristics of the fibroelastomas are analysed and methods for their differential diagnosis from other cardiac tumours are discussed in the context of the available literature.

Aortic Valve↗

PubMedDate not supplied

Rheolytic thrombectomy combined with a protective filter and platelet glycoprotein IIb/IIIa receptor inhibitors in rescue angioplasty.

Rescue angioplasty is used in patients in whom thrombolysis has been unsuccessful, in order to achieve a better restoration of flow and to improve left ventricular function and the long term prognosis. However, patients who undergo rescue angioplasty have a higher rate of reocclusion of the vessel or distal embolism, resulting in increased mortality. Rheolytic thrombectomy, which reduces the quantity of thrombus and improves flow in the vessel, has been used successfully in such cases. We describe a case in which rheolytic thrombectomy was applied during late rescue angioplasty in order to achieve immediate restoration of flow in the vessel.

Angioplasty, Balloon, Coronary↗

PubMedDate not supplied

Ross procedure: medium-term results.

INTRODUCTION: The Ross procedure is a safe alternative option for aortic valve replacement in selected patients. Here we present the medium-term results of our experience with this procedure. METHODS: Between December 1998 and January 2004, 21 patients (16 male, 5 female, mean age 42 years) underwent aortic valve replacement using the Ross operation. Indications for operation were aortic stenosis in 5 patients, aortic regurgitation in 5 patients, aortic stenosis and regurgitation in 9 patients, acute septic endocarditis of a native aortic valve in 1 patient and of a mechanical aortic valve in 1 patient. The root replacement technique was used in 17 patients (81%) and the subcoronary insertion technique in 4 patients (19%). RESULTS: Hospital mortality was 4.7% (1 patient) and late mortality is zero. Mean follow up duration was 4 years (range 1-6 years). On follow up all of the patients were in New York Heart Association class I. One patient developed neo-aortic root dilatation (5.1 cm) with mild neo-aortic valve regurgitation and underwent a modified David I procedure using a Valsalva graft. None of the patients had a gradient of more than 10 mmHg through the pulmonary autograft. Sixteen patients had no aortic insufficiency, while mild aortic regurgitation developed in three patients. Pulmonary valve regurgitation developed in 11 patients (range 8-75 mmHg) but only one patient (75 mmHg) developed significant asymptomatic stenosis. CONCLUSIONS: Our experience with the Ross procedure suggests that aortic root replacement with a pulmonary autograft can be performed safely in adult patients. Pulmonary homograft degeneration requiring reintervention might be a rare complication.

Adolescent↗