We read with interest the study by Klein et al .1 exploring the effect of a less invasive device in inducing left ventricular reconstruction in failing hearts post‐myocardial infarction. Left ventricular remodelling following an anterior myocardial infarction has detrimental effects to the efficacy of the left ventricle. This stems not only from the Laplace law but in addition from the impaired blood flow kinetics within the remodelled left ventricle. The concept of surgical volume reduction of the dilated left ventricle is to exclude the infarcted myocardial tissue, reshape and increase the efficacy of the left ventricle.2 This strategy faces two major challenges.

First, the final end‐diastolic volume should be reduced enough in order to allow the Laplace low to take place effectively. However, the final volume should not be that small, otherwise restrictive phenomena will occur, stroke volume will be reduced, left ventricular filling pressures will rise and re‐dilatation of the left ventricle might occur. In those cases, any potential benefit from volume reduction therapies will be eliminated.3, 4 In order to avoid the left ventricular excessive volume reduction during the procedure, surgeons are trying to keep the final left ventricular remaining volume close to 60 mL/m² using the ‘balloon sizing’ technique. However, even if it is true that a final volume at that level is sufficient for the normally working heart, we still do not know whether this is also true for an impaired left ventricle that has undergone remodelling.

The second challenge for left ventricular reconstruction surgeries is the restoration of a more conical shape of the left ventricle. Studies have shown that a conical shape results in better outcomes since this shape improves blood flow hydrodynamics. In the STICH trial, left ventricular geometry worsened after left ventricular reconstruction surgery and the left ventricle became more spherical.5 Only those patients that obtained a conical left ventricular shape demonstrated improved outcomes.

Left ventricular reconstruction surgery is not a one size fits all patients, and a more individualized approach should be implemented. Klein et al .1 in a less invasive approach attempted to reduce the volume of the infarcted left ventricle, excluding the non‐functioning scarred myocardium. There was a significant reduction in left ventricular volumes and a significant increase in left ventricular ejection fraction. A total of 46 out of 86 participants were characterized as ‘responders’ since they revealed improvement in the 6‐min walk test and in their quality of life.

To the direction of a more individualized approach for ventricular volume reduction and reshaping therapies, it would be very helpful if authors could provide also parameters of the shape of the left ventricle before and following the application of the device (apical conicity index, left ventricular sphericity index). The device proposed by Klein et al .1 has the advantage of requiring no cardiopulmonary bypass. In that way, haemodynamic parameters obtained by a Swan–Ganz catheter at the time of the deployment of the device could provide important prognostic information on the short‐ and long‐term adaptation of the left ventricle to the newly acquired volume and shape in a real time way.

Again, we find the study of Klein et al .1 a very important step for a more quantitative and personalized application of left ventricular reshaping and volume reduction therapies.

我们感兴趣地阅读了Klein等人的研究。1探索一种微创设备在心肌梗死后衰竭心脏诱发左心室重建中的作用。心肌梗塞后左心室重塑对左心室的功效有不利影响。这不仅源于拉普拉斯定律，还源于重塑的左心室内血流动力学受损。减少扩张的左心室手术体积的概念是排除梗塞的心肌组织，重塑形状并增加左心室的功效。2该战略面临两个主要挑战。

首先，应使最终舒张末期容积足够减少，以使拉普拉斯低压有效发生。但是，最终体积不能太小，否则会出现限制性现象，中风量会减少，左心室充盈压会升高，并且可能会导致左心室重新扩张。在那些情况下，减少体积疗法的任何潜在好处将被消除。3，4为了避免在手术过程中左心室容积过大，外科医生试图将最终的左心室剩余容积保持在60 mL / m ^2附近使用“气球尺码”技术。但是，即使确实该水平的最终体积足以正常工作的心脏，我们仍然不知道对于已经历重塑的受损左心室是否也是如此。

左心室重建手术的第二个挑战是恢复左心室更锥形的形状。研究表明，锥形形状可改善结果，因为这种形状可改善血流的流体动力学。在STICH试验中，左心室重构手术后左心室几何结构恶化，左心室变得更球形。5只有那些获得了圆锥形左心室形状的患者才显示出改善的结局。

左心室重构手术并非适合所有患者的一种方法，应采取更具个性化的方法。克莱恩等。1以较小的侵入性方法尝试减少梗塞的左心室体积，但无功能的瘢痕心肌除外。左心室容积显着减少，左心室射血分数显着增加。86名参与者中有46名被称为“响应者”，因为他们发现6分钟步行测试和生活质量有所改善。

对于更加个体化的减少心室体积和重塑疗法的方法的方向，如果作者在使用该装置之前和之后还可以提供左心室的形状参数（顶锥度指数，左心室球形度）将非常有帮助。指数）。该设备由Klein等人提出。图1的优点是不需要体外循环。通过这种方式，在设备部署时由Swan–Ganz导管获得的血液动力学参数可以提供有关真实的左心室短期和长期适应新获得的体积和形状的重要预后信息。时间方式。

同样，我们发现了Klein等人的研究。1对于左心室重塑和缩小体积疗法的定量和个性化应用而言，这是非常重要的一步。