Yanaka Kenichi, Nakayama Kazuhiko, Taniguchi Yu, Onishi Hiroyuki, Matsuoka Yoichiro, Nakai Hidekazu, Okada Kenji, Shinke Toshiro, Emoto Noriaki, Hirata Ken-Ichi
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.
Department of Cardiology, Shinko Hospital, Kobe, Japan.
Int J Cardiol Heart Vasc. 2022 Apr 18;40:101031. doi: 10.1016/j.ijcha.2022.101031. eCollection 2022 Jun.
Right ventricular (RV) afterload is widely assessed by pulmonary vascular resistance (PVR). However, RV afterload is underestimated because PVR does not account for the pulsatile load. The pulsatile load is often evaluated by pulmonary arterial compliance (PAC). The RC (resistance-compliance) time, which is calculated from the product of PVR and PAC, is considered to remain constant under medical therapy. However, little is known on how RC time is affected by invasive therapy in chronic thromboembolic pulmonary hypertension (CTEPH). This study aimed to evaluate change of RC time in patients underwent pulmonary endarterectomy (PEA). Furthermore, we investigated the clinical relevance of RC time.
We reviewed consecutive 50 patients except for death case underwent PEA. Baseline clinical parameters including RC time before performing PEA and follow-up were evaluated. Patients was classified as decrease or non-decrease according to change of RC time. Furthermore, we classified patients into a NYHA I group who had no symptom after treatment and a residual symptom group in order to investigate the relationship of RC time to residual symptoms.
RC time was significantly decreased after PEA (0.54 ± 0.16 to 0.45 ± 0.12 sec, p < 0.001). Residual symptom after PEA of Decrease group were significantly better than that of Non-decrease group in RC time (12 patients, 40% vs. 11 patients, 78.6%, p < 0.02). Furthermore, multivariate analysis revealed that only RC time after PEA was independently associated with residual symptom (OR 1.026, 95% CI 1.005-1.048; p = 0.017).
RC time was decreased after PEA, and might be a possible indicator for predicting PEA success.
右心室（RV）后负荷通常通过肺血管阻力（PVR）进行广泛评估。然而，由于PVR未考虑搏动负荷，RV后负荷被低估。搏动负荷通常通过肺动脉顺应性（PAC）进行评估。由PVR和PAC的乘积计算得出的RC（阻力 - 顺应性）时间在药物治疗下被认为保持恒定。然而，关于慢性血栓栓塞性肺动脉高压（CTEPH）中RC时间如何受到侵入性治疗的影响知之甚少。本研究旨在评估接受肺动脉内膜剥脱术（PEA）患者的RC时间变化。此外，我们还研究了RC时间的临床相关性。
我们回顾了连续50例接受PEA且排除死亡病例的患者。评估了包括PEA术前和随访时的RC时间在内的基线临床参数。根据RC时间的变化将患者分为降低组和未降低组。此外，为了研究RC时间与残余症状的关系，我们将患者分为治疗后无症状的NYHA I组和残余症状组。
PEA术后RC时间显著降低（从0.54±0.16秒降至0.45±0.12秒，p<0.001）。降低组PEA后的残余症状在RC时间方面显著优于未降低组（12例患者，40% 对11例患者，78.6%，p<0.02）。此外，多因素分析显示，仅PEA术后的RC时间与残余症状独立相关（OR 1.026，95%CI 1.005 - 1.048；p = 0.017）。结论：PEA术后RC时间降低，可能是预测PEA成功的一个潜在指标。
