Читать книгу Practical Cardiovascular Medicine - Elias B. Hanna - Страница 45

In trials of initial invasive vs. initial conservative strategy, low-risk women without elevated troponin, ST changes, or high TIMI risk score had a higher risk of death/MI with an invasive strategy than a conservative strategy (significant in RITA 3, non-significant trend in FRISC II).^64,132 However, high-risk women derive a benefit from an initial invasive strategy (TACTICS, meta-analysis).^62,133 While an initial invasive strategy is not indicated in low-risk men either, a meta-analysis shows that an initial invasive strategy is not harmful to low-risk men but is harmful to low-risk women.¹³¹ This is related to the fact that women have less extensive CAD than men in general, and that in these trials of NSTE-ACS, ~24% of women vs. 8% of men randomized to an invasive strategy had no significant CAD, and even among women with elevated troponin, 15–20% had no significant CAD.^133,134 In fact, women have a higher burden of macro- or microvascular spasm. Even among women with CAD, three-vessel or left main disease is less common than among men. In addition, women have a higher bleeding risk, particularly at the vascular access site, which attenuates the benefit from an invasive strategy. Women also have a higher complication rate with CABG.⁶⁴

Despite less extensive CAD, less positive troponin, and less common STEMI presentation relative to NSTE-ACS,¹³⁵ the mortality of women with ACS is equal to that of men, and may be higher on unadjusted analyses (GUSTO IIb analysis) or in the specific case of STEMI.¹³⁵ Women with ACS are older and have more comorbidities (diabetes, diastolic HF) than men. They have a higher BNP and a higher burden of dynamic ST changes on continuous ECG monitoring than men, indicative of a significant ischemic burden despite less CAD and less troponin rise (MERLIN-TIMI trial).¹³⁴ In fact, even among women without obstructive CAD, ~14% have dynamic ST changes on continuous ECG monitoring. Ranolazine may be of particular benefit in women with angina.¹³⁴