Stent implantation in human coronary arteries. Clinical and angiographic aspects

Atherosclerotic cardiovascular disease remains one of the most important causes of morbidity and mortality in the industrialized world. Treatment is basically aimed at palliation and consists of either pharmacological intervention or revascularization. The frrst significant advances in the latter were largely surgical [!]. However, the pressing need for treatment with less invasive and potentially less expensive techniques, have stimulated the development of non-surgical revascularization techniques. Percutaneous transluminal coronary balloon angioplasty, which was first performed by Andreas Gruentzig in 1977, is one of the most successful examples and provided the stimulus for a rapid technological growth of interventional cardiology [2]. It is now widely accepted as a safe and effective treatment of obstructive coronary artery disease. However, the risk of abrupt vessel closure during or immediately after the intervention and the risk of late luminal renarrowing or restenosis continue to compromise its overall safety and efficacy [3,4]. To improve the immediate and long-term results of balloon angioplasty, a number of new technologies such as intracoronacy stenting, directional or rotational atherectomy and laser therapy have been developed and represent the leading edge in the battle against atherosclerosis [5-8]. The intracoronary stent has been shown to be effective in the treatment of acute or threatened vessel closure due to balloon angioplasty induced coronary dissection, alleviating the need for emergency bypass surgery [9]. Furthermore, it has been hypothesized that intracoronary stent implantation may reduce the incidence of restenosis by optimizing the immediate angiographic results which should lead to improved long-term clinical outcome

Incidence, predictors, and management of acute coronary occlusion after coronary angioplasty

Acute coronary occlusion occurs in 4.3% to 8.3% of patients during coronary angioplasty. Its occurrence is difficult to predict in an individual patient. At high risk are patients with unstable angina, intracoronary thrombus, extreme age, long complex lesions, and diffuse disease. "Standard" management including redilation (prolonged perfusion) thrombolytic treatment and emergency bypass surgery is only successful in approximately 50% of the patients and is associated with a high mortality and myocardial infarction rate of < 6% and 30%, respectively. Bail-out stent implantation appears to emerge as an effective alternative in suitable patients and might reduce mortality, the apparent progression to myocardial infarction, or might decrease the need for emergency bypass. New techniques including directional atherectomy, rotational ablation, or the excimer laser are associated with a similar frequency of acute occlusion. Immediate access to a surgical back-up facility remains necessary to treat refractory acute occlusions

Should all patients with an acute myocardial infarction be referred for direct PTCA?

All randomised comparisons have shown that direct PTCA is superior to thrombolysis in patients with AMI. Yet the choice of treatment strategy should depend on the careful evaluation of the risk/benefit of treatment. Issues unrelated to this assessment will most likely influence the selection of treatment in daily practice. Two algorithms have been proposed which differ in the primary selection or triage criterion (area at risk versus time interval). Based upon local and regional factors, one or the other may be chosen. The role of rescue and systematic PTCA after thrombolysis needs further elucidation. At present, it cannot be proposed as a standard treatment

Case report: Concomitant MitraClip implantation for severe mitral regurgitation and plug closure of endocarditis induced fistula between aortic root and left atrium after transcatheter aortic valve implantation

Background: Infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) occurs in up to 1.5% of patients within the first year. The development of an aorto-atrial fistula (AAF) is a rare but problematic complication of IE, which can be confirmed with transoesophageal echocardiography (TOE). We present an exceptional case of occluding an aorto-left atrial fistula only diagnosed with intraprocedural TOE during a subsequent procedure of MitraClip implantation. Case summary: A 79-year-old symptomatic male patient with multiple comorbidities was referred due to severe mitral regurgitation (MR). He has had prior TAVI which was complicated with streptococcal IE for which he had received prolonged antibacterial therapy. Transthoracic echocardiography (TTE) revealed severe MR. The patient was accepted for a MitraClip procedure by the heart team. Intra-procedural TOE revealed also a significant continuous shunt through an AAF which was likely caused by the endocarditis. The strategy was therefore defined as to occlude the fistula with an Amplatzer Vascular Plug II 12 mm. The plug was released in the fistula leaving an insignificant residual shunt. After the transseptal puncture one MitraClip XTR was implanted, reducing the MR to mild. After the procedure, the patient's general clinical condition improved without signs of haemolysis. The pre-discharge TTE confirmed trace residual shunt, mild residual MR and mild paravalvular leakage. Discussion: Our case illustrates a complex transcatheter structural heart intervention with improvised procedural strategies based on the intra-procedural TOE findings. We conclude that the pre-procedural TOE needs to be comprehensive rather than exclusive, particularly in the context of bioprosthesis-related endocarditis

Response of conductance and resistance coronary vessels to scalar concentrations of acetylcholine: Assessment with quantitative angiography and intracoronary Doppler echography in 29 patients with coronary artery disease

Abnormal vasoreactivity of the large conductance arteries has been observed in the presence of impaired endothelial function. More recently, experimental and clinical reports have shown that in early coronary atherosclerosis the impairment of the endothelium-mediated vasodilatation also involves the resistance arteries. The aim of this study is the correlation of endothelium-dependent vasodilatation of conductance and resistance vessels in coronary arteries without significant stenoses. In 29 patients (aged 57 +/- 9 years, 24 men and 5 women) undergoing coronary angioplasty, a Doppler guide wire and a perfusion catheter were introduced into the proximal segment of an artery with less than 30% diameter stenosis. Selective infusions of papaverine (bolus of 7 mg), acetylcholine (continuous infusion of 0.036, 0.36, and 3.6 micrograms/ml at a flow rate of 2 ml/min), and isosorbide dinitrate (bolus of 3 mg) were sequentially performed. Heart rate, aortic blood pressure, and blood flow velocity were continuously measured. Mean cross-sectional areas of a proximal and a distal arterial segment were measured in baseline conditions, at the end of each infusion of acetylcholine, and at the peak effect of isosorbide dinitrate with quantitative angiography (CAAS System; Pie Medical Data, Maastricht, The Netherlands). Coronary blood flow was calculated from the time-averaged flow velocity and the cross-sectional area at the site of the Doppler sample volume. Coronary flow resistance was calculated as mean aortic pressure divided by coronary flow. All of the concentrations of acetylcholine induced a significant vasoconstriction of the studied artery. At the maximal concentration of acetylcholine all but three patients (90%) showed a reduction of cross-sectional area (-24% +/- 20% and -22% +/- 20% for the proximal and distal segments, respectively, p < 0.00001). Flow velocity showed a significant increase only with the two highest concentrations of acetylcholine. The maximal concentration induce

Comparative angiographic quantitative analysis of the immediate efficacy of coronary atherectomy with balloon angioplasty, stenting, and rotational ablation

Interventional cardiology has branched in two directions: devices that primarily dilate coronary stenoses and those that debulk coronary tissue. Presently the optimum coronary intervention has not been found. While patients are awaiting randomized trials, a comparison based on matched quantitative coronary analysis may be useful to evaluate results of new interventional techniques. Therefore we compared 51 patients undergoing atherectomy with individually matched patients who were undergoing balloon angioplasty and stenting. The lesions were matched according to location of stenosis and reference diameter. Atherectomy and stenting resulted in larger gains in minimal luminal diameter compared with conventional balloon angioplasty. The minimal luminal diameter was increased from 1.2 +/- 0.4 mm to 2.6 +/- 0.4 mm in the atherectomy group and from 1.2 +/- 0.3 mm to 1.9 +/- 0.4 mm in the angioplasty group (p less than 0.00001). Atherectomy and stenting resulted in similar gains in minimum luminal diameter (1.4 mm vs 1.3 mm, p = NS). In addition, atherectomy and stenting appear to be more effective in resisting elastic recoil because of tissue removal and an intrinsic dilating effect, respectively. In matched populations directional atherectomy and stenting appear to be more effective intracoronary interventional devices than balloon angioplasty based on the immediate results. However, atherectomy is limited in smaller coronary vessels because of its larger size

Women fare no worse than men 10 years after attempted coronary angioplasty.

A retrospective review of cardiac events occurring in all patients who underwent attempted coronary angioplasty in the first 5 years of our experience (1980-1985) was undertaken. Follow-up data were obtained from the civil registry, hospital records, patient, family, and referring physician. Patient survival curves were constructed and the outcome of women and men was compared. Eight hundred fifty-six patients, 172 women and 684 men with a mean age of 60.0 and 55.3 years, respectively, underwent attempted coronary angioplasty with an overall procedural success rate of 82%, 77.7% in women and 83.1% in men. Follow-up data were obtained in 837 patients (97.8%) with a mean period of 9.6 years (range 0-13.3 years). The estimated 10 year survival in women was identical to men [79%, 95% confidence interval (CI) 72.6–85.4% vs. 78%, 95% C

Acute and long-term outcome of directional coronary atherectomy for stable and unstable angina

The clinical efficacy and safety of directional coronary atherectomy for the treatment of stable and unstable angina were assessed in 82 patients with stable and 68 patients with unstable angina. Therefore, clinical and angiographic follow-up was obtained in a prospectively collected consecutive series of 150 atherectomy procedures. Restenosis was assessed clinically and by quantitative angiography. The overall clinical success rate of atherectomy for patients with unstable and stable angina was 88% and 91%, respectively. No significant differences were found for in-hospital event rates between the unstable and stable angina groups: death (1.5% vs 0%), myocardial infarction (10% vs 6%), and emergency bypass operation (3% vs 2%). These clinical events were related to the occurrence of abrupt occlusions (8.8% in patients with stable and 6.1% in those with unstable angina; p = NS). Clinical follow-up was achieved in 100% of the patients with stable and unstable angina at a mean interval of 923 and 903 days, respectively. Two-year survival rates were 96% and 97% in the populations with unstable and stable angina, respectively. There were no significant differences with respect to bypass surgery and angioplasty, but event-free survival at 2 years was significantly lower in the unstable (54%) than the stable (69%) angina group. Quantitative coronary angiography did not detect any difference in luminal renarrowing during the 6-month angiographic follow-up period. Although directional coronary atherectomy can be performed effectively in patients with unstable and stable angina, the long-term clinical outcome was less favorable in the unstable angina group.(ABSTRACT TRUNCATED AT 250 WORDS

Maximal blood flow velocity in severe coronary stenosis measured with a doppler guidewire. Limitations for the application of the continuity equation in the assessment of stenosis severity

In vitro and animal experiments have shown that the severity of coronary stenoses can be assessed using the continuity equation if the maximal blood flow velocity of the stenotic jet is measured. The large diameter and the low range of velocities measurable without frequency aliasing with the conventional intracoronary Doppler catheters precluded the clinical application of this method for hemodynamically significant coronary stenoses in humans. This article reports the results obtained using a 12 MHz steerable angioplasty guidewire in a consecutive se