The Role of the Collateral Circulation in Stable Angina: An Invasive Placebo-Controlled Study.

This placebo-controlled, n-of-1 study investigated the relationship between ischemia, the collateral circulation, and symptoms in stable coronary artery disease.

这项安慰剂对照的n-of-1研究调查了在稳定型冠状动脉疾病中，缺血、侧支循环与症状之间的关系。

Additionally, it explored the association between progressive collateral recruitment and ischemic preconditioning.

此外，它探讨了渐进性侧支循环招募与缺血预处理之间的关联。

Methods

Fifty-one participants with severe single-vessel coronary artery disease and angina were recruited.

招募了51名患有严重单血管冠状动脉疾病和心绞痛的参与者。

Antianginal medications were stopped, and daily angina symptoms were documented using a dedicated smartphone application (ORBITA [Objective Randomized Blinded Investigation With Optimal Medical Therapy of Angioplasty in Stable Angina] app) for 14 days before undergoing invasive pressure wire studies and coronary flow reserve assessment.

抗心绞痛药物被停止，使用专用智能手机应用程序（ORBITA [客观随机盲法研究，最佳药物治疗下经皮冠状动脉介入治疗在稳定型心绞痛中的应用]应用程序）记录了术前14天的每日心绞痛症状，然后进行侵入性压力导丝研究和冠状动脉储备评估。

Each participant then underwent four 60-s episodes of low-pressure balloon occlusion across their coronary stenosis.

然后每位参与者经历了四个60秒的低压力球囊闭塞其冠状动脉狭窄的阶段。

Each episode was paired with an audiovisually identical placebo inflation in a randomized order.

每次发作都与一个视听上相同的安慰剂膨胀配对，按照随机顺序进行。

After each episode, participants scored pain intensity on a 10-point scale, and a placebo-controlledpain intensity score was calculated.

发作后，参与者使用10点量表评分疼痛强度，并计算了安慰剂对照的疼痛强度评分。

Collateral flow index was calculated from simultaneous measures of aortic, right atrial, and distal coronary wedge pressure during balloon occlusion.

通过在球囊封堵期间同时测量主动脉、右心房和远端冠状动脉楔压来计算侧支血流指数。

Higher Pr values from Bayesian models indicate a greater likelihood of association.

贝叶斯模型中较高的Pr值表明关联的可能性更大。

Results

The mean (±SD) age of participants was 63±9 years, and 78% were men.

参与者的平均年龄为63±9岁，其中78%为男性。

The median (interquartile range) fractional flow reserve was 0.68 (0.57-0.79), the median instantaneous wave-free ratio was 0.80 (0.48-0.89), and the median coronary flow reserve was 1.42 (1.08-1.85).

中位数（四分位数间距）的分数流量储备为0.68（0.57-0.79），瞬时无波段比率的中位数为0.80（0.48-0.89），冠状动脉储备流量的中位数为1.42（1.08-1.85）。

Daily angina frequency showed little correlation with severity of ischemia, as assessed by fractional flow reserve (Somers' D 0.124, Pr=0.057) or instantaneous wave-free ratio (Somers' D 0.056, Pr=0.150).

每日心绞痛发作频率与通过分数流量储备（Somers' D 0.124, Pr=0.057）或瞬时无波比（Somers' D 0.056, Pr=0.150）评估的缺血严重程度相关性不大。

However, there was strong evidence of an association between lower fractional flow reserve and instantaneous wave-free ratio values and greater collateral flow (Somers' D 0.302, Pr=0.998 and Somers' D 0.316, Pr=0.999, respectively).

然而，有强有力的证据表明，较低的分数流量储备和瞬时无波比值与较大的侧支血流相关（Somers' D 0.302, Pr=0.998 和 Somers' D 0.316, Pr=0.999，分别）。

There was also strong evidence of an association between more collateralization (higher collateral flow index) and lower pain intensity scores (Somers' D 0.341, Pr=0.999).

在更多的侧支循环（较高的侧支血流指数）与较低的疼痛强度评分之间存在强烈的关联证据（Somers' D 0.341, Pr=0.999）。

Finally, pain intensity scores and collateral flow index remained stable between sequential balloon occlusion episodes within individual patients, indicating little evidence of ischemic preconditioning.

最后，疼痛强度评分和侧支血流指数在个别患者中在连续的球囊闭塞发作期间保持稳定，表明缺血预处理的证据很少。

Conclusions

Coronary collateralization is associated with ischemic burden and may reduce the intensity of ischemic chest pain.

冠状动脉侧支循环与缺血负荷相关，并可能减轻缺血性胸痛的强度。

This may explain the nonlinear relationship between stenosis, ischemia, and angina.

这可能解释了狭窄、缺血和心绞痛之间的非线性关系。

registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04280575.

网址: https://www.clinicaltrials.gov; 唯一标识符: NCT04280575.