Background-Rapid loss of collateral support has been reported after percutaneous coronary intervention (PCI), leaving the myocardium susceptible to subsequent infarction. However, well-developed collaterals have been found in normal hearts, suggesting that collaterals exist even in the absence of an ischemic stimulus. We assessed the plasticity and determinants of collateral supply after PCI. Methods and Results-Collateral flow index (CFI) was calculated in 60 patients as (P w ϪP v )/(P a ϪP v ) by measurement of aortic (P a ), central venous (P v ), and coronary wedge (P w ) pressures. CFI was reassessed during transient balloon occlusion 5 minutes and 24 hours after PCI in the first 29 patients and at 6 months in the subsequent 25 patients. We also evaluated the relationship between collateral supply, lesion characteristics, and circulating hemopoietic cells numbers before and after successful PCI. CFI at baseline was 0.23Ϯ0.10, with no change 5 minutes and 1 day later (0. 21Ϯ0.12, Pϭ0.62; and 0.22Ϯ0.11, Pϭ0.96, respectively). At 6 months, CFI was 0.14Ϯ0.07 or 63Ϯ27% of the baseline value (PϽ0.001). CFI was proportional to severity of the coronary lesion at baseline (rϭ0.63, PϽ0.0001) but not 6 months after PCI (rϭϪ0.04, Pϭ0.87). The number of circulating CD133 ϩ and CD34 ϩ cells was associated with CFI 6 months after PCI (CD133, rϭ0.59, Pϭ0.035; CD34, rϭ0.63, Pϭ0.037). Conclusions-Coronary collateral flow remains undiminished for at least 24 hours after successful PCI. Functional collateral support subsequently declines but does not regress completely.

Objective: To evaluate whether a well developed collateral circulation predisposes to restenosis after percutaneous coronary intervention (PCI). Design: Prospective observational study. Patients and setting: 58 patients undergoing elective single vessel PCI in a tertiary referral interventional cardiac unit in the UK. Methods: Collateral flow index (CFI) was calculated as (P w 2 P v )/(P a 2 P v ), where P a , P w , and P v are aortic, coronary wedge, and right atrial pressures during maximum hyperaemia. Collateral supply was considered poor (CFI , 0.25) or good (CFI > 0.25). Main outcome measures: In-stent restenosis six months after PCI, classified as neointimal volume > 25% stent volume on intravascular ultrasound (IVUS), or minimum lumen area ( 50% stent area on IVUS, or minimum lumen diameter ( 50% reference vessel diameter on quantitative coronary angiography. Results: Patients with good collaterals had more severe coronary stenoses at baseline (90 (11)% v 75 (16)%, p , 0.001). Restenosis rates were similar in poor and good collateral groups (35% v 43%, p = 0.76 for diameter restenosis, 27% v 45%, p = 0.34 for area restenosis, and 23% v 24%, p = 0.84 for volumetric restenosis). CFI was not correlated with diameter, area, or volumetric restenosis (r 2 , 0.1 for each). By multivariate analysis, stent diameter, stent length, . 10% residual stenosis, and smoking history were predictive of restenosis. Conclusion: A well developed collateral circulation does not predict an increased risk of restenosis after PCI.T he potential of coronary collaterals to abrogate myocardial ischaemia and limit infarction has long been established. 2Similarly, a well developed collateral circulation appears to predict an improved clinical outcome after percutaneous coronary intervention (PCI). When a dichotomous collateral flow index (CFI) threshold of 0.25 is used to distinguish between good and poor collateral supply, patients with inadequate collateral protection have been shown to have a four-to eightfold increase in the rate of death, myocardial infarction, or unstable angina after PCI compared with those with adequate collaterals.3 4 In contrast to the beneficial association between coronary collaterals and clinical sequelae, the impact of collateral flow at the time of PCI on subsequent restenosis remains controversial. Several retrospective studies have suggested that good collateral flow is a risk factor for restenosis.5-7 It has been postulated that this may be due to reduced antegrade flow in the target vessel caused by competitive flow through persistent collateral channels. More recent reports have failed to reproduce these findings. Much of this controversy may relate to the methods used in these studies. In early reports, the collateral circulation was characterised by coronary wedge pressure (P w ) or angiographically visible channels, which are imprecise techniques and have largely been superseded. 5 6 All these studies have relied on a dichotomous angiographic definition of restenosis, which is relatively insensit...

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The study identified training needs of apple growers in district Budgam, J&K. Purposive sampling technique was used to select two blocks (Beerwah and Khan Sahib), four zones, eight circles and eighty apple farmers were selected for the study. Some of the data were analyzed with percentage and mean score while some were presented in charts. Majority (77.5%) of the respondents did not have contact with extension agents in 2012 and they sourced information apple from neighbours (86.3%).The mean annual expenditure and income from apple were Rs. 27, 568 and Rs. 235, 530, respectively. Majority (96.2%) of the respondents had no training on processing and preservation of apple and off season production of apple (85%). Majority of the respondents indicated that training on apple should be organized by researchers (65%) through interpersonal communication (83.8%) using local language (kashmiri) (78.8%). Provision of effective micro-credit facilities (M=2.84) and stability of government policy (stability of price of apple) (M=2.68) were perceived by the respondents as major strategies that will improve apple production in the area. The study encouraged building capacities of apple farmers through informal training especially in the areas of processing, preservation and off-season production of apple so that they can face challenges of the enterprise, boost their farm size and income.