Stress cardiac magnetic resonance (CMR) in the management of coronary chronic total occlusion (CTO) disease: first data from PECTO (PEscara CTO) Registry
Background Methods Results Conclusions
Successful CTO PCI resulted in improved symptoms, left ventricular function and prognosis. The aim of our study was to determine whether stress MRI assessment of inducible myocardial ischemia and viability in the area supplied by a CTO can improve the selection of patients that can benefit from CTO PCI.
We studied 20 patients (aged 39-76 years) with angiography identified CTO. Adenosine stress MRI was performed before and two months after CTO PCI.
Significative inducible perfusion defect (> 10%) and viability of the myocardium supplied by the CTO were indications for the CTO PCI. EF, angina pectoris and pro-BNP were evaluated both before and after the procedure, in order to assess their functional status. Segmental strain analysis was performed. A total of 15 patients showed a 10% inducible perfusion defect in the territory of the RCA and underwent CTO PCI with an anterograde, retrograde or mixed approach. One procedure failed. An increase of EF was found in follow-up(45 ± 7 % vs. 52± 6,05 %; p < 0.001). A decrease in angina grading(p < 0.001) and NYHA class (p = 0.001) was observed and pro-BNP levels decreased (p-value < 0.05)after CTO-PCI.The CMR showed a reduction of the telediastolic indexed volume of the left ventricle of 27.95% (93.97 ± 26.88 ml/m2 vs. 67.43 ± 21.25 ml/m2; p < 0.001); ejection fraction improved by 31.76% in controls (43.56 ± 16.57% vs. 57.4 ± 3.45%; p < 0.001). The Late gadolinium enhancement (LGE) values also showed no significant variation, either in terms of absolute mass in grams or in percentage terms. A reduction of the perfusional deficit in its reversible proportion has also been documented (p<0.05).
Adenosine stress MRI has proven to be an accurate method for a patient suitable selection for CTO PCI. Segmental strain analysis could provide significant information about transmurality of ischemic damage. CTO PCI showed an efficacy not only in reducing the symptomatology, probably in relation to the significant reduction of the perfusional defect responsible for triggering the painful process, but also in improving functional capacity with an increase in systolic performance and reduction of endoventricular volume, thus acting also on the diastolic performance.