經導管主動脈瓣膜氣球擴張術治療主動脈瓣膜狹窄

Percutanoues Balloon Aortic Valvuloplasty for Aortic Stenosis

主動脈瓣膜狹窄（aortic stenosis）為進行性的主動脈瓣膜退化疾病，其盛行率在65歲以上病患可達2％。一旦重度主動脈瓣膜狹窄病患出現症狀，若沒有接受及時的介入治療，這些病患的預後極差。在過去，開心手術置換主動脈瓣膜（surgical aortic valve replacement, SAVR）是重度主動脈瓣狹窄的標準治療。然而，許多手術高風險的病患因無法接受傳統開心手術而死亡。法國醫師Alain Cribier在1986年為了解決這個問題，在一位重度主動脈狹窄合併心因性休克的病患身上，進行了首例經導管主動脈瓣膜氣球擴張術（percutaneous balloon aortic valvuloplasty, BAV）。該病患心衰竭症狀獲得了顯著地改善。但後續的研究顯示，因為主動脈瓣膜再狹窄比率過高，導致BAV並無法成功降低病患的死亡率。相對於BAV，經導管主動脈瓣膜置換術（transcatheter aortic valve replacement, TAVR）則是提供了持續且可靠的治療效果。然而，在目前TAVR盛行的年代，BAV仍然有其角色存在。BAV可以作為重度主動脈瓣膜狹窄病患合併血液動力學不穩定時的過渡性治療，讓病患可以在穩定後接受SAVR或TAVR。BAV亦可以作為評估重度主動脈瓣膜狹窄病患合併多重疾病時，其臨床症狀是否能靠降低經主動脈瓣壓力差而獲得改善的診斷工具。整體而言，在TAVR逐漸興起的年代，BAV雖不能作為單獨的治療手段，還是佔有重要且不可取代的地位。 Aortic stenosis is a progressive disease that affects 2% of the population aged 65 years or older. Patients with symptomatic severe aortic stenosis have very poor prognosis if not having timely intervention. Surgical aortic valve replacement (SAVR) reduces symptoms and improves survival. However, in clinical practice, at least 30% of patients with severe symptomatic aortic stenosis do not undergo surgery for replacement of the aortic valve, owing to advanced age, left ventricular dysfunction, or the presence of multiple coexisting conditions. Percutaneous balloon aortic valvuloplasty (BAV) was widely adopted when first described by Alain Cribier et al in 1986. However, its popularity waned as it emerged that restenosis and recurrence of symptoms were common after 6 months and mortality rates within a year of BAV were similar to those of an untreated conservatively managed population. Transcatheter aortic valve replacement (TAVR) provided the solution for these patients. In the TAVR era, BAV can’t be considered a destination treatment for severe aortic stenosis patients. Instead, BAV should be used as a bridge to SAVR or TAVR for patients with hemodynamic instability. It also can become a screening tool to evaluate whether TAVR is a futile therapy to frail population or patients with multiple comorbidities. Overall, BAV is now used not only in aortic valve pre-dilation for TAVR but has taken on an expanded role with a broader recognition of its palliative benefits and means for a bridge to SAVR or TAVR.