Takemoto Masao, Yoshimura Hitoshi, Ohba Yurika, Matsumoto Yasuharu, Yamamoto Umpei, Mohri Masahiro, Yamamoto Hideo, Origuchi Hideki
Internal Medicine, Kyushu Kosei-Nenkin Hospital, Kitakyushu, Japan.
J Am Coll Cardiol. 2005 Apr 19;45(8):1259-65. doi: 10.1016/j.jacc.2004.12.073.
The present study evaluated clinical benefits of radiofrequency catheter ablation (RFA) for premature ventricular complexes from right ventricular outflow tract (RVOT-PVC) in patients without structural heart disease.
It is unknown whether PVC causes left ventricular (LV) dilation, which is a well-recognized precursor of LV dysfunction and heart failure, and whether eliminating PVC by RFA produces clinical benefits in patients with RVOT-PVC.
Frequency of PVC per total heart beats by 24-h Holter monitoring, left ventricular ejection fraction (LVEF), left ventricular end-diastolic internal dimension (LVDd), mitral regurgitation (MR) by echocardiogram, cardiothoracic ratio (CTR) by chest radiogram, and New York Heart Association (NYHA) functional class of 40 patients with RVOT-PVC without structural heart disease were evaluated before and 6 to 12 months after RFA.
Before RFA, a subgroup of patients with frequent (>20%) PVC demonstrated significantly enlarged LVDd and CTR, reduced LVEF, increased MR, and deteriorated NYHA functional class as compared to the subgroup with rare (<20%) PVC (54 +/- 1 mm vs. 45 +/- 1 mm, 52 +/- 2% vs. 46 +/- 1%, 66 +/- 2% vs. 73 +/- 2%, 1.2 +/- 0.2 degree vs. 0.4 +/- 0.1 degree, and 1.8 +/- 0.2 vs. 1.3 +/- 0.1, respectively; p < 0.05). Furthermore, ablating RVOT-PVC readily produced the improvement of all these abnormalities (47 +/- 1 mm, 41 +/- 1%, 72 +/- 2%, 0.3 +/- 0.1 degree, and 1.0 +/- 0.0, respectively; p < 0.05 compared with before RFA).
These findings suggest that frequent (>20%) RVOT-PVC may be a possible cause of LV dysfunction and/or heart failure, and RFA produces clinical benefits in these patients.
本研究评估了射频导管消融术（RFA）对无结构性心脏病患者右心室流出道室性早搏（RVOT-PVC）的临床益处。
目前尚不清楚PVC是否会导致左心室（LV）扩张，而左心室扩张是公认的左心室功能障碍和心力衰竭的先兆，以及通过RFA消除PVC是否会给RVOT-PVC患者带来临床益处。
通过24小时动态心电图监测评估40例无结构性心脏病的RVOT-PVC患者在RFA术前以及术后6至12个月时每总心搏的PVC频率、左心室射血分数（LVEF）、左心室舒张末期内径（LVDd）、超声心动图检测的二尖瓣反流（MR）、胸部X线片检测的心胸比率（CTR）以及纽约心脏协会（NYHA）心功能分级。
RFA术前，频发（>20%）PVC的患者亚组与偶发（<20%）PVC的患者亚组相比，LVDd和CTR显著增大，LVEF降低，MR增加，NYHA心功能分级恶化（分别为54±1mm对45±1mm、52±2%对46±1%、66±2%对73±2%、1.2±0.2级对0.4±0.1级、1.8±0.2对1.3±0.1；p<0.05）。此外，消融RVOT-PVC后，所有这些异常情况均得到明显改善（分别为47±1mm、41±1%、72±2%、0.3±0.1级、1.0±0.0；与RFA术前相比，p<0.05）。
这些发现表明，频发（>20%）RVOT-PVC可能是左心室功能障碍和/或心力衰竭的一个可能原因，并且RFA对这些患者有临床益处。
