Five-year results of the complete versus culprit vessel percutaneous coronary intervention in multivessel disease using drug-eluting stents II (CORRECT II) study: a prospective, randomised controlled trial.

OBJECTIVES/BACKGROUND: In patients with multivessel coronary artery disease (MVD) the decision whether to treat a single culprit vessel or to perform multivessel revascularisation may be challenging. The purpose of this study was to evaluate the long-term outcome of multivessel percutaneous coronary intervention (MV-PCI) versus culprit vessel only (CV-PCI) in patients with stable coronary artery disease or non-ST elevation acute coronary syndrome. METHODS: In this dual-centre, prospective, randomised study a total 215 patients with MVD were randomly assigned to MV-PCI or CV-PCI. The primary endpoint was the occurrence of major adverse cardiac events (MACE) including death, myocardial infarction (MI), and repeat revascularisation. Secondary endpoints were the combined endpoint of death or MI, the individual components of the primary endpoint, and the occurrence of stent thrombosis. Patients were followed up to 5 years after enrolment. RESULTS: The occurrence of the primary endpoint was similar at 28% versus 31% in the MV-PCI and CV-PCI group, respectively (hazard ratio [HR] 0.87, 95% confidence interval [CI]: 0.53-1.44, p = 0.59). The rate of repeat revascularisation was 15% versus 24% (HR 0.59, 95% CI 0.32 to 1.11, p = 0.11), whereas definite or probable stent thrombosis occurred in 2% versus 0% (p = 0.44). CONCLUSIONS: In this randomised study comparing the strategies for MV-PCI and CV-PCI in patients with MVD, no difference was found in the occurrence of MACE after 5 years. We observed a numerically higher rate of death or MI and a lower rate of repeat revascularisation after MV-PCI, although these findings were not statistically significant.

Impact of percutaneous coronary intervention timing on 5-year outcome in patients with non-ST-segment elevation acute coronary syndromes. The 'wait a day' approach might be safer.

BACKGROUND: The OPTIMA trial was a randomised multicentre trial exploring the influence of the timing of percutaneous coronary intervention (PCI) on patient outcomes in an intermediate to high risk non-ST-elevation acute coronary syndrome (NSTE-ACS) population. In order to decide the best treatment strategy for patients presenting with NSTE-ACS, long-term outcomes are essential. METHODS: Five-year follow-up data from 133 of the 142 patients could be retrieved (94 %). The primary endpoint was a composite of death and spontaneous myocardial infarction (MI). Spontaneous MI was defined as MI occurring more than 30 days after randomisation. Secondary endpoints were the individual outcomes of death, spontaneous MI or re-PCI. RESULTS: No significant difference with respect to the primary endpoint was observed (17.8 vs. 10.1 %; HR 1.55, 95 % CI: 0.73-4.22, p = 0.21). There was no significant difference in mortality rate. However, spontaneous MI was significantly more common in the group receiving immediate PCI (11.0 vs. 1.4 %; HR 4.46, 95 % CI: 1.21-16.50, p = 0.02). We did not find a significant difference between the groups with respect to re-PCI rate. CONCLUSION: There was no difference in the composite of death and spontaneous MI. The trial suggests an increased long-term risk of spontaneous MI for patients treated with immediate PCI.

Antithrombotic therapy in patients undergoing TAVI: an overview of Dutch hospitals.

PURPOSE: To assess current antithrombotic treatment strategies in the Netherlands in patients undergoing transcatheter aortic valve implantation (TAVI). METHODS: For every Dutch hospital performing TAVI (n = 14) an interventional cardiologist experienced in performing TAVI was interviewed concerning heparin, aspirin, thienopyridine and oral anticoagulation treatment in patients undergoing TAVI. RESULTS: The response rate was 100 %. In every centre, a protocol for antithrombotic treatment after TAVI was available. Aspirin was prescribed in all centres, concomitant clopidogrel was prescribed 13 of the 14 centres. Duration of concomitant clopidogrel was 3 months in over two-thirds of cases. In 2 centres, duration of concomitant clopidogrel was based upon type of prosthesis: 6 months versus 3 months for supra-annular and intra-annular prostheses, respectively. CONCLUSIONS: Leaning on a small basis of evidence and recommendations, the antithrombotic policy for patients undergoing TAVI is highly variable in the Netherlands. As a standardised regimen might further reduce haemorrhagic complications, large randomised clinical trials may help to establish the most appropriate approach.

Outpatient coronary stent implantation.

OBJECTIVES: This study was performed to explore the feasibility of coronary Palmaz-Schatz stent implantation on an outpatient basis. BACKGROUND: To optimize the applicability of coronary stenting by limiting bleeding complications and length of hospital stay, the transradial approach has been demonstrated to be an effective technique. Immediate ambulation opens the way to outpatient treatment. METHODS: Patients selected for Palmaz-Schatz stent implantation received anticoagulation with Coumadin. At an international normalized ratio > 2.5, stenting was performed through the radial approach. Starting in December 1994, patients were treated with Ticlopidin. Heparin was administered during the procedure. Suitability for same-day discharge was assessed on the basis of preprocedural, postprocedural and periprocedural criteria. Patients were mobilized after immediate sheath removal, followed by same-day discharge. Follow-up examinations were performed the next day, at 2 weeks and at 1 month after stenting. RESULTS: Of 188 patients who underwent Palmaz-Schatz coronary stent implantation through the radial artery between May 1994 and July 1995, 88 remained in the hospital for various reasons. In the 100 outpatients (Canadian Cardiovascular Society classes III and IV, n = 90 [90%]), 125 stents had been implanted to cover 110 lesions. No cardiac or bleeding events were encountered within 24 h (95% confidence interval 0 to 3.6) of stenting. At 2-week follow-up, one patient was readmitted (day 4) because of a bleeding abdominal aortic aneurysm requiring operation. Two patients were readmitted 2 weeks after discharge, one with subacute thrombosis and one with angina and anemia that was treated with blood transfusions. At 1-month follow-up, no complications were observed. CONCLUSIONS: After an optimal transradial Palmaz-Schatz coronary stent result, patients can safely be discharged on the day of treatment.

A randomized comparison of percutaneous transluminal coronary angioplasty by the radial, brachial and femoral approaches: the access study.

OBJECTIVES: This study sought to compare procedural and clinical outcomes of percutaneous transluminal coronary angioplasty (PTCA) performed with 6F guiding catheters introduced through the radial, brachial or femoral arteries. BACKGROUND: Transradial PTCA has been demonstrated to be an effective and safe alternative to transfemoral PTCA; however, no randomized data are currently available. METHODS: A randomized comparison between transradial, transbrachial and transfemoral PTCA with 6F guiding catheters was performed in 900 patients. Primary end points were entry site and angioplasty related. Secondary end points were quantitative coronary analysis after PTCA, procedural and fluoroscopy times, consumption of angioplasty equipment and length of hospital stay. RESULTS: Successful coronary cannulation was achieved in 279 (93.0%), 287 (95.7%) and 299 (99.7%) patients randomized to undergo PTCA by the radial, brachial and femoral approaches, respectively. PTCA success was achieved in 91.7%, 90.7% and 90.7% (p = NS) of patients, with 88.0%, 87.7% and 90.0% event free at 1-month follow-up, respectively (p = NS). Major entry site complications were encountered in seven patients (2.3%) in the transbrachial group, six (2.0%) in the transfemoral group and none in the transradial group (p = 0.035). Transradial PTCA led to asymptomatic loss of radial pulsations in nine patients (3%). Procedural and fluoroscopy times were similar, as were consumption of guiding and balloon catheters and length of hospital stay ([mean +/- SD] 1.5 +/- 2.5, 1.8 +/- 3.8 and 1.8 +/- 4.2 days, respectively). CONCLUSIONS: With experience, procedural and clinical outcomes of PTCA were similar for the three subgroups, but access failure is more common during transradial PTCA. Major access site complications were more frequently encountered after transbrachial and transfemoral PTCA.

Prognostic value of dipyridamole sestamibi single-photon emission computed tomography and dipyridamole stress echocardiography for new cardiac events after an uncomplicated myocardial infarction.

A high-dose dipyridamole stress test (0.84 mg/kg in 6 minutes) with simultaneous sestamibi single-photon emission computed tomographic (SPECT) and echocardiographic imaging was performed in 89 patients before hospital discharge after an uncomplicated myocardial infarction. The aim of this study was to determine the prognostic value of these tests for new cardiac events and to compare the relative values of SPECT and echocardiography in a postinfarction dipyridamole stress test. Two years after infarction, nine patients (10%) had died, five patients (6%) had suffered a nonfatal reinfarction, and 14 patients (16%) had been readmitted to the hospital for a revascularization procedure. Cardiac death had occurred in 5 (10%) of 48 patients with a positive SPECT versus 4 (10%) of 41 with a negative SPECT (difference not significant) and in 6 (19%) of 31 with a positive echocardiogram versus 3 (5%) of 56 with a negative echocardiogram (p = 0.05). Cardiac death or reinfarction had occurred in 8 (17%) of 48 patients with a positive SPECT versus 6 (15%) of 41 with a negative SPECT (difference not significant) and in 6 (19%) of 31 with a positive echocardiogram versus 8 (14%) of 56 with a negative echocardiogram (difference not significant). Thus the predictive value of the dipyridamole stress test for new cardiac events after an uncomplicated myocardial infarction was limited, irrespective of the method used to detect ischemia. Reversible perfusion defects were identified more frequently than new wall motion abnormalities but did not predict late events. A positive dipyridamole echocardiogram was associated with a higher late mortality rate but did not predict other cardiac events.

Transradial Palmaz-Schatz coronary stenting on an outpatient basis: results of a prospective pilot study.

BACKGROUND: The applicability of Palmaz Schatz coronary stent implantation is limited by bleeding complications and prolonged hospitalization. Coronary stenting on an outpatient basis, may be the ultimate means to reduce costs of this treatment. Since bleeding and stent occlusion were infrequent complications in a group of 100 ambulatory patients who underwent stent implantation via the radial artery in our department, we performed a pilot study to determine the feasibility of using coronary stenting on an outpatient basis. METHODS: Patients selected for Palmaz Schatz stent implantation, were adequately adjusted on coumadin. At an INR > 2.5, stenting was performed via the radial approach. Based on pre-, post- and procedural criteria, considering clinical status, procedural course and outcome, absence of predictors for stent occlusion and of events during 4 to 6 hours observation, patients were considered candidates for same-day discharge. Heparin was administered only during the procedure. Immediately after the procedure, the arterial sheath was removed. Patients were mobilized and were discharged with a pressure dressing over the puncture site. Follow-up was performed on the next day, at 2 weeks and at one month. RESULTS: Between May and September 1994, 47 patients underwent Palmaz Schatz stent implantation via the radial artery. Of these, 27 remained hospitalized for reasons, considered to be incompatible with outpatient treatment. Twenty patients (CCS-class III and IV; n = 17 (85%)) received 29 stents for 23 lesions, distributed in 21 vessels and were discharged the day of treatment. No cardiac or bleeding events were encountered within 24 hours. At 2 weeks follow-up, one patient was readmitted (day 4) because of a bleeding abdominal aortic aneurysm, requiring surgery. At 1 month follow-up, no bleeding, entry-site and cardiac complications were noted. CONCLUSION: Since no complications were encountered (95% confidence interval; 0-17%) in the first 24 hours after optimal coronary stent implantation in patients with an adequate preprocedural level of anticoagulation, a larger feasibility study of outpatient coronary stenting will be undertaken.

[Percutaneous transluminal mitral valvuloplasty using the double balloon technic]. / Percutane transluminale mitralis-valvuloplastiek met behulp van de dubbele-ballontechniek.

This paper describes the results in 3 patients with rheumatic mitral stenosis, who underwent percutaneous transluminal mitral valvuloplasty, using the double balloon technique. The clinical outcome after 6 months' follow-up is favourable. The procedure is effective and relatively safe, if careful patient selection takes place using echocardiography and cardiac catheterisation. Balloon dilatation of a stenotic mitral valve may be an attractive alternative to surgical open or closed commissurotomy.

Safety, efficacy and costs associated with direct coronary stenting compared with stenting after predilatation: A randomised controlled trial.

OBJECTIVES: Comparison of the in-hospital success rates, procedural costs and short-term clinical outcomes of direct stenting versus stenting after balloon predilatation. METHODS: Altogether, 400 patients with angina pectoris and/or myocardial ischaemia due to coronary stenoses in a single native vessel were randomised to either direct stenting or stenting after predilatation. Baseline characteristics were evenly distributed between the two groups. RESULTS: Procedural success rates were similar (96.0% direct stenting group vs. 94.5% predilatation) as well as final successful stent implantation (98.3 vs. 97.8%), while the primary success rate of direct stenting alone was 88.3%, p=0.01. In multivariate analysis, angiographic lesion calcification was an independent predictor of unsuccessful direct stenting (odds ratio 7.1, 95% confidence interval 2.8-18.2, p<0.0001). Rates of troponin I rises >0.15 µg/l, used as a measure of distal embolisation, were similar in both groups (17.8 vs. 17.1%). Rates of major adverse cardiac events at 30 days were 4.5% in the direct stenting group versus 5.5% in the predilated group (ns). Direct stenting was associated with savings in fluoroscopy time, and angiographic contrast agent use, and a reduction in utilisation of angioplasty balloons (0.4 vs. 1.17 balloons per patient, p<0.001). Mean per patient procedural costs associated with direct stenting versus predilatation were €2545±914 versus €2763±842 (p=0.01), despite the implantation of more stents in the directly stented group. CONCLUSION: Compared with a strategy of stenting preceded by balloon predilatation, direct stenting was equally safe and effective, with similar in-hospital and 30-day clinical outcomes, and modest procedural cost-savings. A calcified lesion predicted unsuccessful direct stenting.

Diagnostic and therapeutic approach of congenital solitary coronary artery fistulas in adults: Dutch case series and review of literature.

BACKGROUND: Coronary artery fistulas (CAFs) are infrequent anomalies, coincidentally detected during coronary angiography (CAG). AIM: To elucidate the currently used diagnostic imaging modalities and applied therapeutic approaches. MATERIALS AND METHODS: Five Dutch patients were found to have CAFs. A total of 170 reviewed subjects were subdivided into two comparable groups of 85 each, treated with either percutaneous 'therapeutic' embolisation (PTE group) or surgical ligation (SL group). RESULTS: In our series, the fistulas were visualised with several diagnostic imaging tests using echocardiography, multidetector computed tomography, and CAG. Four fistulas were unilateral and one was bilateral; five originated from the left and one originated from the right coronary artery. Among the reviewed subjects, high success rates were found in both treatment groups (SL: 97% and PTE: 93%). Associated congenital or acquired cardiovascular disorders were frequently present in the SL group (23%). Bilateral fistulas were present in 11% of the SL group versus 1% of the PTE group. The fistula was ligated surgically in one and abolished percutaneously in another. Medical treatment including metoprolol was conducted in two, and watchful waiting follow-up was performed in one. CONCLUSIONS: Several diagnostic imaging techniques are available for assessment of the anatomical and functional characteristics of CAFs.

Immediate versus deferred coronary angioplasty in non-ST-segment elevation acute coronary syndromes.

BACKGROUND: The field of acute coronary syndromes is characterised by an increasing tendency towards early invasive catheter-based diagnostics and therapeutics-a practice based on observational and retrospective data. OBJECTIVE: To compare immediate versus deferred angioplasty in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) METHODS: A randomised, prospective multicentre trial was performed in patients admitted with NSTE-ACS, eligible for percutaneous coronary intervention (PCI). Interim analysis was performed after enrolment of 251 patients; PCI was appropriate in 142 patients. These patients were randomised to immediate PCI (n = 73) or deferred PCI (24-48 h) (n = 69). Patients received protocol-driven glycoprotein IIb/IIIa blockers, aspirin and clopidogrel. The primary end point was a composite of death, non-fatal myocardial infarction (MI) or unplanned revascularisation, at 30 days. After hospital discharge outpatient follow-up was performed at 30 days and 6 months. RESULTS: The incidence at 30 days of the primary end point was 60% in the group receiving immediate PCI and 39% in the group receiving deferred PCI (relative risk (RR) = 1.5, 95% CI 1.09 to 2.15; p = 0.004). No deaths occurred in either group. MI was significantly more common in the group receiving immediate PCI (60% vs 38%, RR = 1.6, 95% CI 1.12 to 2.28, p = 0.005). Unplanned revascularisation was similar in both groups. The observed difference was preserved over 6-months' follow-up. CONCLUSIONS: Immediate PCI was associated with an increased rate of MI in comparison with a 24-48 h deferred strategy, despite aggressive antithrombotic treatment. The results suggest that PCI for high-risk patients with non-refractory NSTE-ACS should be delayed for at least 24 h after hospital admission. TRIAL REGISTRATION NUMBER: ISRCTN80874637.

Mode of deployment of coronary Palmaz-Schatz stents after implantation with the stent delivery system: an intravascular ultrasound study.

The stent delivery system (SDS) is a sheath-covered Palmaz-Schatz stent mounted on a 3.0, 3.5, or 4.0 mm compliant polyethylene balloon catheter; the balloon resists maximal inflation pressures of 5.7, 6.2, or 6.0 atm, respectively. It is postulated that these pressures are too low to obtain optimal stent deployment. Because optimal stent deployment is a prerequisite for optimal short- and long-term outcome, we performed an intravascular ultrasound study to the mode of stent deployment after delivery with the SDS and after high-pressure dilatations with low-compliant, oversized balloon catheters. In 23 patients an intravascular ultrasound study (30 MHz, 4.3F transducer) was performed to the geometry of 29 stents immediately after delivery with the SDS and after successive high-pressure inflations with low-compliant balloons. After delivery with the SDS (3.3 +/- 0.4 mm), stent diameter was 3.0 +/- 0.4 mm. After high-pressure dilatations (12.4 +/- 1.4 atm) with low-compliant balloons (3.9 +/- 0.5 mm), stent diameter increased to 3.4 +/- 0.4 mm (p < 0.001). Only 8 (28%) stents were completely and symmetrically expanded to the corresponding reference diameter with good apposition after delivery with the SDS. Diameter of incomplete deployed stents (n = 16) was 2.8 +/- 0.3 mm. After high-pressure dilatations with low-compliant balloons (3.9 +/- 0.5 mm), diameter increased to 3.4 +/- 0.4 mm (p < 0.001). Now 20 (69%) stents (p = 0.004) became completely and symmetrically expanded to a diameter corresponding to the reference diameter. In conclusion, most stents are suboptimally deployed after delivery with the stent delivery system.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous transradial coronary Palmaz-Schatz stent implantation, guided by intravascular ultrasound.

Intravascular ultrasound (IVUS) allows accurate assessment of stent deployment, its use being confined to the use of 8 French (F) guiding catheters. We evaluated the feasibility of combining transradial artery Palmaz-Schatz stent implantation through 6F guiding catheters with IVUS for assessment of stent diameter after delivery at moderate inflation pressures (10-12 atmospheres [atm]) with compliant balloons and after high pressure dilatations with balloons of intermediate compliance. In 8 consecutive patients, 12 stents were delivered with Scimed Express balloon catheters at 10-12 atm followed by IVUS (EndoSonics CathScanner; Visions FX 3.5F 20 MHz transducer). An ultrasound study was repeated after high pressure dilatations (16-20 atm) with Schneider Magical Speedy balloon catheters. The balloon diameters were derived from manufacturer provided specifications. In all patients the transducer could easily be advanced through the guiding catheters. Reference diameter of the stented segment was 3.7 +/- 0.5 mm (2.7-4.5) and the diameter of Scimed Express balloons during inflation was 4.0 +/- 0.3 mm (3.6-4.7). Stent diameter was 3.0 +/- 0.1 mm (2.8-3.2) (P < 0.001 compared to the reference and the balloon diameter). The diameter of the Schneider Magical Speedy balloons at secondary dilatations with 16 +/- 3 atm (14-20) was 4.1 +/- 0.4 mm (3.3-4.5) (P = 0.50 compared to the initial balloon diameter). Final stent diameter was 3.3 +/- 0.4 mm (2.9-4.1) (P = 0.02 compared to the initial stent diameter). All stents were symmetrically deployed and well apposed. No damage to vessel or stents was detected after passage of the transducer.(ABSTRACT TRUNCATED AT 250 WORDS)

Safety and efficacy of AVE gfx stent implantation via 6 Fr guiding catheters.

This prospective study was designed to determine the feasibility of AVE gfx premounted stent systems in combination with 6 Fr guides. Between 1 April and 12 August 1997, 230 patients underwent AVE gfx coronary stent implantation via 6 Fr guides. The radial approach was used in 146 patients (63.5%). In 230 procedures (293 lesions), 237 guiding catheters were used. A total of 331 AVE gfx stents were implanted, 1.4 per patient. Backup, opacification, and friction were considered good in 85.8%, 96.4%, and 76.7%, respectively. Slight and severe friction was felt during combined use of long (> or = 18 mm), large-sized (3.5 mm) stents and small-sized guiding catheters (inner diameter, 0.061-0.062"). The presence of a second protecting guidewire impaired passage of the AVE gfx stent, also in large 6 Fr guides (ID 0.064"). Of 331, 320 (96.7%) stents were successfully deployed at the initial attempt. Ten stents (3%) had to be retrieved. Six of these were successfully placed at a second attempt and three slipped off the balloon, all successfully retrieved from the patient's circulation. At 1 month, 217 patients (94.4%) were free of events. The AVE gfx stent is compatible with 6 Fr guiding catheters. Use of new-generation, large-bore 6 Fr gc (> or = 0.064") is recommended.

Actual outpatient PTCA: results of the OUTCLAS pilot study.

This study tested the safety and feasibility of coronary angioplasty on an outpatient basis. The purpose of this approach includes cost-effectiveness and patient comfort. Included were 159 patients treated with balloon angioplasty or intracoronary stent placement, all performed via the radial artery with 6 French guiding catheters. Patients were selected for same-day discharge based on the absence of any adverse predictor for subacute occlusion or unfavorable clinical outcome during the first 24 hr after successful PTCA. One hundred and six (66%) patients were discharged 4-6 hr after PTCA. Stents were used in 40% of patients. There were no cardiac or vascular complications. We conclude that outpatient PTCA, performed via the radial artery, is both safe and feasible in a large part of a routine PTCA population.

A pilot study of coronary angioplasty in outpatients.

BACKGROUND: Is it safe to discharge patients from hospital on the same day as percutaneous transluminal coronary angioplasty (PTCA)? The hypothesis tested was that careful pre and post angioplasty selection of patients can identify a group that is at very low risk of postprocedural complications and that these patients may be discharged on the day of the procedure. METHODS: 63 patients undergoing limited risk coronary angioplasty of 72 lesions were studied. So that patients would be able to walk soon after PTCA miniature equipment (6 French catheters and balloon-on-a-wire devices) was passed percutaneously through the right brachial artery. After coronary angioplasty patients with angiographic evidence of dissection and/or thrombus and with complications were assigned to an inpatient group and those in whom PTCA had achieved a good angiographic result were assigned to an outpatient group. RESULTS: Two patients were excluded because the brachial approach failed, leaving 61 patients (70 lesions). After PTCA 50 patients (82%) with 57 lesions (81%) attempted were assigned to the outpatient group. No cardiac complication occurred in this subset (0%; 95% confidence interval 0 to 7%). Eleven patients (18%), in whom 13 lesions (19%) were attempted, were assigned to the inpatient group. Three of these patients (27%; 95% confidence interval 6 to 61%) had cardiac complications. Two patients needed local surgical repair after catheterisation of the brachial artery; one had a haematoma and one had a false aneurysm. CONCLUSIONS: Coronary angioplasty with miniature equipment passed through the brachial artery was a safe procedure with a high initial success rate. The results of this pilot trial suggest that with careful selection of patients before and after angioplasty PTCA can be performed safely in outpatients.

Incidence and outcome of radial artery occlusion following transradial artery coronary angioplasty.

Coronary angioplasty with 6F guiding catheters via the radial artery is associated with a minimal risk for major entry site-related complications. Although the incidence of radial artery occlusion (RAO) in the literature is approximately 30% after prolonged cannulations, little is known about the incidence and its clinical consequences of RAO following transradial percutaneous coronary angioplasty. In a prospective study, 563 patients with a normal Allen test were evaluated on patency and function of the radial artery after transradial angioplasty, by physical and ultrasound examination at discharge, and at 1 month follow-up. At discharge, 30 patients (5.3%) had clinical evidence of RAO. At follow-up, persistent RAO was found in 16 patients (2.8%). In this study we found a low incidence of RAO after transradial percutaneous coronary angioplasty. None of the patients with temporary or persistent RAO had any major clinical symptoms. Therefore, the occurrence of RAO can be considered a minor complication in patients with a previously good double blood supply to the hand.