629 research outputs found
Anion-channel blockade with alinidine: a specific bradycardic drug for coronary heart disease without negative inotropic activity
In 14 patients undergoing cardiac catheterization for suspected coronary artery disease, alinidine, 0.6 mg/kg, was administered intravenously to determine its effects on left ventricular (LV) function, coronary blood flow and myocardial oxygen consumption. To assess effects independent of changes in heart rate (HR), measurements were made at spontaneous and matched pacing HRs. At spontaneous HR, alinidine decreased HR from 70 +/- 2 to 61 +/- 3 beats/min (p less than 10(-6]. Peak rate of LV pressure decreased from 1,652 +/- 92 to 1,371 +/- 80 mm Hg/s (p less than 10(-5] and Vmax decreased from 47 +/- 3 to 41 +/- 2 s-1 (p less than 10(-4]. Coronary sinus blood flow decreased from 109 +/- 9 to 89 +/- 7 ml/min (p less than 0.01) and myocardial oxygen consumption from 10.9 +/- 1.0 to 9.0 +/- 0.8 ml O2/min (p less than 0.05). At a matched pacing HR of 98 +/- 3 beats/min before and after alinidine administration, peak rate of LV pressure decreased from 1,984 +/- 124 to 1,793 +/- 106 mm Hg/s (p less than 10(-4] and Vmax from 60 +/- 5 to 56 +/- 4 s-1 (p less than 0.02). Coronary sinus blood flow and myocardial oxygen consumption were not significantly changed at matched pacing HRs. The time constant of the first 40 ms of LV isovolumic relaxation was prolonged by alinidine only during spontaneous HR. Thus, alinidine results in a bradycardia-dependent decrease in myocardial oxygen consumption. It has negative inotropic properties independent of changes in HR and so is not a pure bradycardia-specific agent
Intracoronary Blood Flow Velocity and Transstenotic Pressure Drop in an Awake Human Being During Coronary Vasodilation
The pressure drop over a coronary stenosis and the intracoronary Doppler blood flow velocity were measured at rest and during coronary vasodilation. We report the first observation that confirms the validity of fluid dynamic equations to describe the hemodynamics of a coronary stenosis based on quantitative arteriography in a human being. (J Interven Cardiol 1988:1:1) Copyrigh
Frontiers in interventional cardiology
n more than 20 years since the first percutaneous coronary revascularization procedures, the field of interventional cardiology has proliferated beyond all expectations. Now more than 1 million procedures are performed worldwide each year. Stenting has revolutionized the field, which previously relied on balloon dilatation in the majority of patients. With 50% of patients now undergoing stent implantation, the groundwork is laid for further important advances. In this article, we discuss the 4 most important new advances in the field of interventional cardiology: platelet inhibition, prevention of restenosis, stent evolution, and angiogenesis
Drug-eluting stents: current issues
Early stent thrombosis occurs in about 1% to 1.5% of patients with drug-eluting stents, very similar to the rate with bare-metal stents. Late stent thrombosis is more of a concern with drug-eluting stents, with an incidence of at least 0.35%. I would urge caution if you feel you have to stop antiplatelet therapy in patients with drug-eluting stents. While neointima formation peaks at 6 months and then may actually regress with bare-metal stents, it continues to grow with drug-eluting stents--although this process appears to plateau by 4 years with sirolimus. With the others, we have to wait and see. We still don't know the best drug-eluting stent. Trials are under way to compare stents with surgery, and the future brings the arrival of a number of exciting new devices and approaches that are now entering clinical trials
Transluminal coronary angioplasty : an investigational tool and a non operative treatment of acute myocardial ischemia
Since the introduction of coronary angioplasty in 1977, this procedure has gained
increasing importance in the treatment of coronary artery obstruction. From the
available evidence it can be estimated that this therapeutic tool will gain even
more momentum from the tens of thousands of patients who will be treated in the
next few years. Information about the indications, benefits and risks of the
coronary angioplasty is accumulating rapidly, in addition to publications about
refinements of the technique itself.
Recently, a number of investigators have realised that coronary angioplasty, is
not only a therapeutic tool, but can, during the procedure. be used as a source of
diagnostic information. When the catheter is placed across a coronary artery
obstruction, inflation of the balloon produces transient myocardial ischemia.
Before, during and after this period of severe ischemia studies of the performance
of the myocardium at risk can be carried out.
The fact that therapeutic coronary angioplasty is carried out in a cardiac
catheterization laboratory, which is by definition optimally equipped for the
measurements of hemodynamic parameters, has probably also contributed to the
execution of these investigations. The combination of hemodynamic and biochemical
parameters with morphological information from the coronary angiogram
can be utilized for the quantification of myocardial involvement and the
success of coronary artery dilatation with angioplasty. Studies of interactions with
pharmacological substances are also feasible and informative.
Coronary angioplasty has a most promising future as an unique means to gather
insight in the intricacies of myocardial oxygen supply and demand in patients with
coronary artery disease
Who was thrombogenic: the stent or the doctor?
In 1986, when pioneers such as Jacques Puel and Ulrich Sigwart implanted the first coronary Wallstents, no guidelines were available to determine the treatment after stenting. From the experience acquired with mechanical prosthetic heart valves, it was inferred that chronic anticoagulation with coumarins was indicated. When the first cases of subacute occlusion were encountered, the anticoagulation regimen was further reinforced. The use of heparin, dextran, or thrombolytic agents during the procedure followed by warfarin, aspirin, sulphinpyrazone, and dipyridamole did not eliminate subacute thrombosis, which occurred in 18% of the first 117 stents implanted and was responsible for a higher incidence of hemorrhagic complications and prolonged hospital stay
Thrombolysis of acute total occlusion of the left main coronary artery in evolving myocardial infarction
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The Dutch experience in percutaneous transluminal angioplasty of narrowed saphenous veins used for aortocoronary arterial bypass
Of 19,994 percutaneous transluminal coronary angioplasty procedures performed in The Netherlands between April 1980 and January 1989, the long-term follow-up of 454 patients who underwent angioplasty of greater than or equal to 1 saphenous vein bypass graft was reviewed. In 46% of patients single graft angioplasty was attempted, and in 54% of patients sequential graft angioplasty was attempted. The clinical primary success rate was 90%. In-hospital mortality was 0.7%, 2.8% of patients sustained a procedural myocardial infarction, and 1.3% of patients underwent emergency bypass surgery. After a follow-up period of 5 years, 74% of patients were alive, and 26% were alive and event-free (no myocardial infarction, no repeat bypass surgery or repeat angioplasty). In patients in whom the initial angioplasty attempt was unsuccessful, only 3% were event-free at 5 years, versus 27% of successfully dilated patients. The time interval between the angioplasty attempt and previous surgery was a significant predictor for 5-year event-free survival. The event-free survival rates for patients who had bypass surgery 1 year before, between 1 and 5 years, and 5 years before angioplasty, were 45, 25 and 19%, respectively. Less than one-third of patients with previous bypass surgery who had angioplasty of the graft remained event-free after 5 years. In patients needing angioplasty within 1 year after bypass surgery, better long-term results were achieved
Coronary arterial findings after accidental death immediately after successful percutaneous transluminal coronary angioplasty
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