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Dive into the research topics where Alexios P. Dimas is active.

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Featured researches published by Alexios P. Dimas.


American Heart Journal | 1989

Long-term function of the morphologic right ventricle in adult patients with corrected transposition of the great arteries

Alexios P. Dimas; Douglas S. Moodie; Richard Sterba; Carl C. Gill

Because of the concern about the ability of the morphologic right ventricle (MRV) to function over a long term as a systemic ventricle, adult patients with congenitally corrected transposition of the great arteries (CCTGA) were evaluated to determine the long-term function of the MRV. Morphologic right ventricular function was assessed by functional clinical classification and angiographic ejection fraction in 18 adult patients with congenitally corrected transposition of the great arteries. These patients had a mean age of 30.2 +/- 14.5 years (range 10 to 67 years). All but one had hemodynamically significant lesions, the most common being left atrioventricular valve regurgitation (11 patients), ventricular septal defect (seven patients), atrial septal defect (four patients), and pulmonic stenosis (three patients). The mean MRV ejection fraction at presentation was 55% +/- 11.5% (range 24% to 74%). Twelve of the 18 patients (67%) were followed clinically, with a mean follow-up time of 9.9 +/- 7.1 years (range 1 to 22 years). Eight were reassessed angiographically, with a mean MRV ejection fraction of 51.3% +/- 10.7% (range 30% to 67%). The other four were followed up clinically and evaluated by two-dimensional echocardiography, with normal MRV function in two patients. Eight of 12 patients (67%) were in functional class I at follow-up, one was in functional class II, one was in functional class III, and two had died. Our data suggest that the morphologic right ventricle can function appropriately over a long term in adult patients with congenitally corrected transposition of the great arteries.(ABSTRACT TRUNCATED AT 250 WORDS)


American Journal of Cardiology | 2009

Clinical Outcomes of Patients With Diabetic Nephropathy Randomized to Clopidogrel Plus Aspirin Versus Aspirin Alone (A post hoc Analysis of the Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management, and Avoidance [CHARISMA] Trial)

Arijit Dasgupta; Steven R. Steinhubl; Deepak L. Bhatt; Peter B. Berger; Mingyuan Shao; Koon-Hou Mak; Keith A.A. Fox; Gilles Montalescot; Michael A. Weber; Steven M. Haffner; Alexios P. Dimas; P. Gabriel Steg; Eric J. Topol

No prospective randomized trial has specifically examined the long-term outcomes of clopidogrel use in patients with chronic kidney disease. This study aimed to determine the risks and benefits of long-term clopidogrel administration in patients with diabetic nephropathy, the most common form of chronic kidney disease. We performed a post hoc analysis of the CHARISMA trial, which randomly assigned patients without active acute coronary syndrome, but with established atherosclerotic disease (symptomatic) or multiple risk factors for atherosclerotic disease (asymptomatic), to clopidogrel plus aspirin versus placebo plus aspirin. All CHARISMA patients (n = 15,603) were separated into the 3 groups: nondiabetic patients, diabetic patients without nephropathy, and diabetic patients with nephropathy. Within each group, outcomes of patients randomly assigned to clopidogrel were compared with those of patients randomly assigned to placebo. Outcomes in the prespecified CHARISMA subgroups of asymptomatic and symptomatic patients were also compared with respect to study drug assignment and nephropathy status. Patients with nephropathy who received clopidogrel had no difference in bleeding, but experienced significantly increased cardiovascular (CV) and overall mortality compared with those randomly assigned to placebo. There were no differences in bleeding, overall mortality, or CV mortality for nondiabetic or diabetic patients without nephropathy who received clopidogrel versus placebo. In the asymptomatic cohort, patients with nephropathy randomly assigned to clopidogrel had significantly increased overall and CV mortality compared with placebo, whereas asymptomatic patients without nephropathy randomly assigned to clopidogrel had no significant mortality difference compared with placebo. In conclusion, this post hoc analysis suggested that clopidogrel may be harmful in patients with diabetic nephropathy. Additional studies are needed to investigate this possible interaction.


American Journal of Cardiology | 1993

Complications associated with percutaneous placement and use of intraaortic balloon counterpulsation.

Hélène Eltchaninoff; Alexios P. Dimas; Patrick L. Whitlow

In-hospital and late complications related to percutaneous placement of 240 intraaortic balloon pump catheters in 231 consecutive patients from March 1985 through June 1990 were reviewed. Mean age was 64 +/- 11 years and 34% were women. Average duration of counterpulsation was 44.2 hours. Indications for counterpulsation included complications of myocardial infarction (34.6%), prophylactic placement before high-risk coronary angioplasty (20.0%) or open heart surgery (12.9%), complicated coronary angioplasty (18.3%), end-stage cardiomyopathy (5.4%) and miscellaneous (8.8%). Early major complications occurred in 11 cases (4.6%) and included limb ischemia requiring surgery (n = 9), bleeding requiring arterial repair (n = 1) and septicemia (n = 1). Other complications included hematoma requiring transfusion (n = 7), limb ischemia resolving with balloon catheter removal (n = 12), and superficial wound infection (n = 1). Overall in-hospital complication rate was 13% (31 of 240). Peripheral vascular disease and diabetes were found to be significant predictors of limb ischemia (p = 0.01 and p = 0.02, respectively). Follow-up information was obtained in 97% of patients with a mean duration of 19 months: 2 patients (1.1%) required vascular surgery for femoral false aneurysms and 1 patient experienced new onset of claudication. In conclusion, compared with previous experience, contemporary intraaortic balloon counterpulsation with percutaneous placement of smaller size (8.5Fr to 10.5Fr) catheters is associated with improved complication profile. This will further enhance the current trend for an expanding role of intraaortic balloon counterpulsation in complex interventional procedures.


American Heart Journal | 1991

Percutaneous transluminal angioplasty involving internal mammary artery grafts

Alexios P. Dimas; Rohit R. Arora; Patrick L. Whitlow; Jay Hollman; Irving Franco; Russell E. Raymond; Khosrow Dorosti; Conrad Simpfendorfer

With the increasing use of the internal mammary artery as the conduit of choice in coronary bypass surgery, it is anticipated that an expanding patient population will have stenosis, usually at the site of internal mammary-to-coronary artery anastomosis. In our series 31 patients underwent dilatation at either the site of anastomosis (24), the native coronary artery beyond the anastomosis (4), or both (3) with no mortality, myocardial infarction, or need for emergency coronary artery bypass surgery. Angiographic and clinical success was achieved in 28 patients (90%). There were two internal mammary artery dissections with both patients requiring elective coronary bypass surgery. Of the patients in whom dilatation was successful, 22 (79%) have been followed for longer than 6 months and 19 (86%) have had sustained functional improvement at a mean of 35 months after angioplasty. One patient is to undergo repeat coronary bypass surgery. No patient has had a myocardial infarction or died during follow-up. Although percutaneous transluminal coronary angioplasty of the internal mammary artery has inherent difficulties because of the anatomic characteristics of the vessel, it can be performed with a high degree of primary success and a low incidence of complications and can provide long-term clinical improvement.


Journal of the American College of Cardiology | 1999

Relationship of Extent of Revascularization With Angina at One Year in the Bypass Angioplasty Revascularization Investigation (BARI)

Patrick L. Whitlow; Alexios P. Dimas; Thomas M. Bashore; Robert M. Califf; Martial G. Bourassa; Bernard R. Chaitman; Allan D. Rosen; Kevin E. Kip; Michael L. Stadius; Edwin L. Alderman

OBJECTIVES To determine the relative degree of revascularization obtained with bypass surgery versus angioplasty in a randomized trial of patients with multivessel disease requiring revascularization (Bypass Angioplasty Revascularization Investigation [BARI]), one-year catheterization was performed in 15% of patients. BACKGROUND Complete revascularization has been correlated with improved outcome after coronary artery bypass grafting (CABG) but not with percutaneous transluminal coronary angioplasty (PTCA). Relative degrees of revascularization after PTCA and surgery have not been previously compared and correlated with symptoms. METHODS Consecutive patients at four BARI centers consented to recatheterization one year after revascularization. Myocardial jeopardy index (MJI), the percentage of myocardium jeopardized by > or =50% stenoses, was compared and correlated with angina status. RESULTS Angiography was completed in 270 of 362 consecutive patients (75%) after initial CABG (n = 135) or PTCA (n = 135). Coronary artery bypass grafting patients had 3+/-0.9 distal anastomoses and PTCA patients had 2.4+/-1.1 lesions attempted at initial revascularization. At one year, 20.5% of CABG patients had > or =1 totally occluded graft and 86.9% of vein graft, and 91.6% of internal mammary artery distal anastomotic sites had <50% stenosis. One year jeopardy index in surgery patients was 14.1+/-11%, 46.6+/-20.3% improved from baseline. Initial PTCA was successful in 86.9% of lesions and repeat revascularization was performed in 48.4% of PTCA patients by one year. Myocardial jeopardy index one year after PTCA was 25.5+/-22.8%, an improvement of 33.8+/-26.1% (p<0.01 for greater improvement with CABG than PTCA). At one year, 29.6% of PTCA patients had angina versus 11.9% of surgery patients, p = 0.004. One-year myocardial jeopardy was predictive of angina (odds ratio 1.28 for the presence of angina per every 10% increment in myocardial jeopardy, p = 0.002). Randomization to PTCA rather than CABG also predicted angina (odds ratio 2.19, p = 0.03). CONCLUSIONS In this one-year angiographic substudy of BARI, CABG provided more complete revascularization than PTCA, and CABG likewise improved angina to a greater extent than PTCA.


Journal of the American College of Cardiology | 1992

Angioplasty of the proximal left anterior descending coronary artery: Initial success and long-term follow-up

John H. Frierson; Alexios P. Dimas; Patrick L. Whitlow; Jay Hollman; Dominic Marsalese; Conrad Simpfendorfer; Khosrow Dorosti; Irving Franco

From 1984 to 1987, 537 consecutive patients (mean age 58 years; range 34 to 79) underwent angioplasty for proximal left anterior descending coronary artery disease. The procedure was clinically successful in 516 (96.1%). Procedural complications included myocardial infarction (2.2%; Q wave 0.9%, non-Q wave 1.3%), in-hospital bypass surgery (3%) and death (0.4%). Follow-up was obtained in 534 patients (99.8%) for a mean duration of 44 months (range 8 to 75). Follow-up cardiac catheterization, performed in 391 patients (76%), demonstrated a 39.6% angiographic restenosis rate. Ninety-eight (19%) of the patients with a clinically successful result required additional revascularization for recurrent left anterior descending artery disease by angioplasty (12.8%) or coronary artery bypass grafting (4.7%), or both (1.5%). During follow-up there was a 2.5% incidence rate of myocardial infarction (anterior myocardial infarction 1.6%), and 27 patients (5.2%) died, 14 (2.7%) of cardiac causes. The actuarial 5-year cardiac survival rate was 97%, freedom from cardiac death and myocardial infarction was 94% and freedom from cardiac death, myocardial infarction, coronary artery bypass surgery and repeat left anterior descending artery angioplasty was 77%. At last follow-up 76% of patients were free of angina and 88% reported sustained functional improvement. Angioplasty is an effective treatment for proximal left anterior descending coronary artery disease that has a high success rate, low incidence of procedural complications and provides excellent long-term cardiac survival, freedom from cardiac events and sustained functional improvement.


Journal of the American College of Cardiology | 1992

Repeat coronary angioplasty as treatment for restenosis

Alexios P. Dimas; Fernando Grigera; Rohit R. Arora; Conrad Simpfendorfer; Jay Hollman; John H. Frierson; Irving Franco; Patrick L. Whitlow

Repeat coronary angioplasty has become the standard approach to a first restenosis. However, the long-term outcome of such a strategy is not well defined. In the present study, 465 patients (mean age 58 years [range 27 to 79], 53% with multivessel disease) underwent a second angioplasty procedure at the same site. The procedure was successful in 96.8% with a 1.5% rate of in-hospital bypass surgery, a 0.9% incidence rate of myocardial infarction and no procedural deaths. Four hundred sixty-three patients (99.6%) were followed up for a mean of 40.5 months. Forty-nine patients (10.6%) underwent a third angioplasty procedure at the same site, 55 (11.8%) had coronary bypass surgery and 33 (7.1%) underwent angioplasty at a different site. During follow-up, 12 patients (2.6%) sustained a myocardial infarction and 21 (4.5%) died including 13 (2.8%) with cardiac death. Of the 442 surviving patients, 88% experienced sustained functional improvement and 78% were free of angina. The actuarial 5-year cardiac survival rate was 96% and the rate of freedom from cardiac death and myocardial infarction was 92%. For the subgroup of 49 patients who had a third angioplasty procedure at the same site, the success rate was 93.9% with a 2% incidence rate of myocardial infarction. There were no in-hospital deaths or coronary artery bypass operations. The mean follow-up interval for this subgroup was 30.5 months with a 22.4% cross-over rate to coronary bypass surgery, a 4.1% incidence rate of myocardial infarction and a 2% cardiac mortality rate. At last follow-up, 89% of patients had sustained functional improvement and 76% were free of angina. The combined angiographic and clinical restenosis rate was 48%. Repeat angioplasty as treatment for restenosis is an effective approach associated with a high success rate, low incidence of procedural complications, and sustained functional improvement in combination with an acceptable rate of bypass surgery. However, there is a trend toward diminished angioplasty efficacy after a second restenosis. Thus, decisions for further revascularization should be made after careful review of available options.


Angiology | 1986

Balloon rupture during coronary angioplasty.

Conrad Simpfendorfer; Alexios P. Dimas; Adnan Zaidi; Jay Hollman; Irving Franco; Valerie Knezinek; Robert E. Hobbs

Out of a total of 1,500 percutaneous coronary angioplasties (PTCA), 55 (3.6%) were associated with balloon rupture. Lesion calcification was noticed in 7 of these 55 patients (12.7%). Balloon rupture occurred at a mean pressure of 10.7 atmospheres. All balloons were retrieved without difficulty. Intimal tears were noted in 18 (32.7%) cases. Three patients required bypass surgery. In 29 patients restudied angiographically, the restenosis rate was 38%. Balloon rupture during PTCA does not seem to be associated with detrimen tal consequences.


Circulation | 1999

Influence of Pre-PTCA Strategy and Initial PTCA Result in Patients With Multivessel Disease The Bypass Angioplasty Revascularization Investigation (BARI)

Kevin E. Kip; Martial G. Bourassa; Alice K. Jacobs; Leonard W. Schwartz; Frederick Feit; Edwin L. Alderman; Bonnie H. Weiner; Melvin B. Weiss; Mirle A. Kellett; Barry L. Sharaf; Alexios P. Dimas; Roger Jones; George Sopko; Katherine M. Detre

BACKGROUND In PTCA patients with multivessel coronary artery disease, incomplete revascularization (IR) is the result of both pre-PTCA strategy and initial lesion outcome. The unique contribution of these components on long-term patient outcome is uncertain. METHODS AND RESULTS From the Bypass Angioplasty Revascularization Investigation (BARI), 2047 patients who underwent first-time PTCA were evaluated. Before enrollment, all significant lesions were assessed by the PTCA operator for clinical importance and intention to dilate. Complete revascularization (CR) was defined as successful dilatation of all clinically relevant lesions. Planned CR was indicated in 65% of all patients. More lesions were intended for PTCA in these patients compared with those with planned IR (2.8 versus 2.1). Successful dilatation of all intended lesions occurred in 45% of patients with planned CR versus 56% with planned IR (P<0. 001). In multivariable analysis, planned IR (versus planned CR), initial lesions attempted (not all versus all intended lesions attempted), and initial lesion outcome (not all versus all attempted lesions successful) were unrelated to 5-year risk of cardiac death or death/myocardial infarction but were all independently related to risk of CABG. CONCLUSIONS Overall, a pre-PTCA strategy of IR in BARI-like patients appears comparable to a strategy of CR except for a higher need for CABG. Whether the use of new devices may attenuate the elevated risk of CABG in patients with multivessel disease and planned IR remains to be determined.


Journal of the American College of Cardiology | 1993

Percutaneous transluminal coronary angioplasty of one major coronary artery when the contralateral vessel is occluded.

Antoine Lafont; Alexios P. Dimas; Fernando Grigera; Greg Pearce; Michele Webb; Patrick L. Whitlow

OBJECTIVES In 193 patients we evaluated the safety and efficacy of angioplasty of a critical stenosis of the right coronary artery (52 patients) or the left anterior descending coronary artery (141 patients), with the contralateral coronary artery occluded and the circumflex artery being without significant stenosis. BACKGROUND Attempted angioplasty of either the left anterior descending or the dominant right coronary artery when the contralateral vessel is occluded may trigger overwhelming left ventricular dysfunction or hemodynamic collapse, or both. METHODS Immediate and late outcome (33 +/- 18 months) in the study group were compared with outcome in 214 patients who had angioplasty in both the left anterior descending and right coronary arteries and in 194 patients who had coronary artery surgery and were matched for number and location of significant lesions, ejection fraction, age, gender and study period. RESULTS Left ventricular function was normal (38%) or mildly (34%), moderately (22%) or severely (6%) compromised. There were 11 (5.7%) emergency and 5 (2.6%) elective coronary artery operations, 3 (1.6%) myocardial infarctions and 1 in-hospital death in the study group. After discharge there were 25 (13.1%) elective coronary operations, 7 (3.7%) myocardial infarctions and 9 (4.7%) deaths in the study group. The incidence of death and myocardial infarction was similar in all groups, with 80% power to detect a 7% difference in adverse events. The study group had more elective surgery before and after discharge than did the surgical control group (p = 0.02). CONCLUSIONS Dilating one major vessel when the contralateral vessel is occluded appears to be as safe as coronary surgery or two-vessel angioplasty. Incomplete revascularization in study group patients did not impair survival or increase myocardial infarction compared with the angioplasty and surgical control groups.

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Kevin E. Kip

University of South Florida

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