RESUMEN
A patient with distal slow-flow after stenting in the old vein graft intervention was reported. This case is a first in whom guidewire-based serial measurement of pressure-derived fractional flow reserve (FFR(myo)) and thermodilution-based coronary flow reserve (CFR(thermo)) clearly demonstrated the serial change of microvascular circulation. During slow-flow, CFR(thermo) remained in low value despite significant improvement of FFR(myo) from 0.61 to 0.90. After thrombus aspiration and nicorandil injection, coronary flow reestablished immediately. CFR(thermo) improved significantly from 1.3 during slow-flow to 3.6 after restoration of flow.
Asunto(s)
Angioplastia Coronaria con Balón , Circulación Coronaria/fisiología , Reestenosis Coronaria/fisiopatología , Reestenosis Coronaria/terapia , Reperfusión Miocárdica , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Presión Sanguínea/fisiología , Angiografía Coronaria , Reestenosis Coronaria/diagnóstico , Electrocardiografía , Humanos , Masculino , Microcirculación/fisiología , TermodiluciónRESUMEN
BACKGROUND: It is not known whether pretreatment with nicorandil, an ATP-sensitive K+ channel (K(ATP)channel) opener, induces a preconditioning effect independent of increased collateral recruitment. METHODS: Forty-four patients with angina who underwent percutaneous transluminal coronary angioplasty (PTCA) to proximal left anterior descending artery (LAD) stenosis were randomly allocated for pretreatment with an intravenous injection of 80 g/kg nicorandil 5 min before initial ballooning (n=22) or saline (n=22). 99mTc tetrofosmin was injected during balloon inflation, quantitative analysis of occlusion images by SPECT was conducted, and the defect severity score (SS) was calculated. An ECG was recorded during the 2-min inflation to calculate the sum of ST elevation (sigmaST). RESULTS: SigmaST levels were significantly reduced in patients with nicorandil pretreatment compared with control patients (control:1.89+/-0.85 mV nicorandil:1.24+/-0.57 mV, p=0.0052). However, no difference was observed in defect severity (control: 79.0+/-32.5, nicorandil: 98.7+/-48.9 ns). A close correlation was observed between SS and sigmaST in both groups (nicorandil group R(2)=0.505, control group R(2)=0.599). A multivariate regression model demonstrated that both defect severity (p<0.0001) and pretreatment with nicorandil (p<0.001) were significantly related to the level of sigmaST, suggesting a cellular protective effect against ischaemia by nicorandil, independent of myocardial blood flow. CONCLUSION: Nicorandil pretreatment resulted in the induction of myocardial preconditioning independent of the severity of ischaemia.
Asunto(s)
Angioplastia Coronaria con Balón , Agonistas de los Canales de Calcio/uso terapéutico , Precondicionamiento Isquémico Miocárdico/métodos , Isquemia Miocárdica/tratamiento farmacológico , Nicorandil/uso terapéutico , Vasodilatadores/uso terapéutico , Anciano , Angioplastia Coronaria con Balón/métodos , Circulación Colateral , Estenosis Coronaria/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico por imagen , Revascularización Miocárdica , Compuestos Organofosforados , Compuestos de Organotecnecio , Cintigrafía , RadiofármacosRESUMEN
The main aim of this study was to elucidate whether the beneficial effect of antecedent angina is a cellular protective effect or the result of an increase of collateral flow. Of 42 patients with angina who underwent percutaneous transluminal coronary angioplasty (PTCA) for proximal left anterior descending artery (LAD) stenosis, 22 had experienced antecedent anginal pain (AP) within 7 days prior to PTCA. 99mTc-sestamibi was injected during balloon inflation, and quantitative analysis of ischemic severity during coronary occlusion was calculated (SS). An electrocardiogram was recorded during ballooning to calculate the sum of ST elevation (sumST). SumST was significantly reduced in patients with AP compared with patients without AP (1.88+/-0.89 mV vs 1.18+/-0.74 mV, p=0.0088); however, no difference was observed in defect severity. A close correlation was observed between SS and sumST in both groups. The multivariate regression model demonstrated that both a large SS (p<0.0001) and the absence of preceding AP (p=0.001) were significantly related to the elevation of sumST. Recent angina can render the myocardium more resistant to subsequent ischemia during angioplasty and is true preconditioning rather than simply an increase of flow.
Asunto(s)
Angina de Pecho/fisiopatología , Angioplastia Coronaria con Balón , Precondicionamiento Isquémico Miocárdico , Anciano , Circulación Colateral , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/fisiopatología , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Collateral fractional flow reserve (FFR(coll)) is an index to quantify collateral blood flow, derived from coronary pressure measurements. Although well defined theoretically, its direct validation by myocardial perfusion imaging has not been established so far. Validating this index by myocardial perfusion imaging is the main aim of this study. METHODS AND RESULTS: Twenty-four consecutive patients with stable angina and single left anterior descending artery stenosis underwent simultaneous measurement of aortic pressure (P(a)), coronary wedge pressure (P(w)), and central venous pressure (P(v)) during balloon inflation. FFR(coll) was calculated and compared with the extent and severity of the defect during coronary occlusion using (99m)Tc-sestamibi imaging at balloon inflation of the respective coronary artery. Although the pressure-derived collateral indexes (P(w), P(w)/P(a), and FFR(coll)) ranged widely, they were closely correlated with extent and severity scores of the nuclear occlusion images and superior to the ECG for that purpose. Of all parameters, FFR(coll) correlated best with the severity score at imaging (r=-0.88), followed by the P(w)/P(a) ratio (r=-0.74) or P(w) alone (r=-0.69). CONCLUSIONS: FFR(coll), calculated from coronary pressure during balloon occlusion, is highly correlated with the extent and severity of the defect at myocardial perfusion of the territory of the occluded artery and can be used for quantitative assessment of collateral blood flow in conscious humans.