Department of Translational Medicine, Università del Piemonte Orientale, Via Solaroli 17, 28100, Novara, Italy.
Cardiology Division, Azienda Ospedaliera Universitaria "Maggiore Della Carità", Novara, Italy.
Clin Res Cardiol. 2020 Jul;109(7):819-831. doi: 10.1007/s00392-019-01570-3. Epub 2019 Nov 20.
Aortic stenosis is a frequent valvular disease, with transcatheter aortic valve implantation (TAVI) being performed when surgical replacement is at increased risk. However, TAVI-induced effects on myocardial efficiency are unknown. We aimed to investigate changes in LV mechano-energetic pre-/post-TAVI and their prognostic impact.
A total of 46 patients (25 males) received transesophageal and simultaneous radial pressure plus transaortic gradient monitoring before/immediately after prosthesis deployment. Efficiency was computed as external work/potential energy, as derived from LV pressure-volume plots; myocardial oxygen consumption (MVO) was estimated as PWI, i.e. a noninvasively validated alternative for MVO estimation.
TAVI was successful in all patients, peak transaortic gradient decreasing - 40 ± 20 mmHg (p < 0.001). Efficiency improved post-TAVI (+ 0.6 ± 0.12; p = 0.004), with a concomitant PWI reduction (- 16 ± 31%; p < 0.001). When contextualized to fixed PWI value (5 ml/min/100 g), efficiency significantly affected survival (p = 0.029). Over 1026 ± 450-day follow-up, a change in efficiency pre-/post-TAVI ≤ 0.021 (median of the difference) predicted more deaths from any cause (30%) as compared with a change > 0.021 (17%), particularly in those patients with a pre-TAVI mean high-gradient (HG ≥ 40 mmHg) phenotype (p < 0.05). In particular, HG patients exhibited the lowest efficiency/PWI ratio pre-/post-TAVI (p = 0.048), relative to the other aortic stenosis patients, suggestive of an unfavourable matching between cardiac function and metabolic demand, which foreshortens some intrinsic damaged muscle condition in these patients.
LV mechanical efficiency improves immediately post-TAVI, notwithstanding an inhomogeneous mechano-energetic matching among the aortic stenosis patients, which can impact negatively on their long-term prognosis, particularly in those with the HG phenotype.
主动脉瓣狭窄是一种常见的瓣膜疾病，当外科置换风险增加时，会进行经导管主动脉瓣植入术（TAVI）。然而，TAVI 对心肌效率的影响尚不清楚。我们旨在研究 LV 机械-能量在 TAVI 前后的变化及其预后影响。
46 例患者（25 例男性）接受经食管和同时桡动脉压力加经主动脉梯度监测，在植入假体前/后即刻进行。效率是通过 LV 压力-容积图计算的外部功/势能来计算的；心肌耗氧量（MVO）通过 PWI 来估计，即 MVO 估计的一种经过验证的替代方法。
所有患者的 TAVI 均成功，主动脉瓣跨瓣峰值梯度降低了-40±20mmHg（p<0.001）。效率在 TAVI 后改善（+0.6±0.12；p=0.004），同时 PWI 降低（-16±31%；p<0.001）。当将 PWI 值固定在 5ml/min/100g 时，效率显著影响生存率（p=0.029）。在 1026±450 天的随访期间，TAVI 前后效率变化≤0.021（差异中位数）预测更多的任何原因死亡（30%），与变化>0.021（17%）相比，尤其是在那些具有 TAVI 前平均高梯度（HG≥40mmHg）表型的患者中（p<0.05）。特别是，HG 患者的 LV 机械效率/PWI 比值在 TAVI 前后最低（p=0.048），与其他主动脉瓣狭窄患者相比，提示心脏功能和代谢需求之间存在不平衡的匹配，这缩短了这些患者的一些内在受损肌肉状况。
尽管主动脉瓣狭窄患者之间存在不均匀的机械-能量匹配，但 LV 机械效率在 TAVI 后立即改善，这可能对其长期预后产生负面影响，特别是在具有 HG 表型的患者中。
