심실 조기 수축, 예후, Ventricular premature beats(VPBs), prognosis ①

VPBs는 종종 미미한 임상적 중요성을 가진 것으로 여겨지지만(특히 심장 질환의 병력이 없는 환자에서) 대부분의 연구에서 VPB 환자의 사망률이 증가한 것으로 보고되었습니다. 그러나, 심근병증이 없는 환자에서 무증상 VPB의 예방적 치료는 사망률을 향상시키지 못했습니다. 이와 같이, VPB의 존재는 의사에게 추가의 임상 평가 또는 치료를 필요로 하는 잠재적으로 공존하는 심장 질환을 알도록 합니다.

VPBs가 생기는 경우는 다음 2가지로 구분할 수 있습니다.
1. No underlying structural heart disease
2. Underlying structural heart disease

먼저 분명한 심장 질환이 없는 경우입니다.
명백하게 정상 심장인 환자에서 simple VPB의 존재는 다음 연구들에서 설명된 것처럼 사망률의 증가와 관련됩니다.

●In the Atherosclerosis Risk in Communities (ARIC) study of subjects without known heart disease followed for more than 10 years, those with a single VPB on a single two-minute ECG had a greater than twofold increase in mortality from coronary heart disease (CHD) compared with those without any VPBs. A subsequent study from the ARIC group reported a twofold increase in sudden cardiac death (SCD) in patients with VPBs compared with those without VPBs.

●In a study of 45,402 veterans, 3.8 percent had VPBs on a resting ECG. Compared with those without VPBs, patients with VPBs had a significantly higher all-cause mortality (22 versus 39 percent) and cardiovascular mortality (8 versus 20 percent).

●In a meta-analysis of eight prospective observational cohort studies (3629 persons total) without apparent heart disease, the presence of VPBs was associated with a significantly greater likelihood of the combined endpoint of all-cause mortality, cardiovascular mortality, SCD, or development of ischemic CHD (pooled odds ratio [OR] 1.72, 95% CI 1.28-2.31). However, only one of the eight studies used advanced testing (ie, echocardiography or stress testing) to exclude underlying structural heart disease.

●In a separate meta-analysis of 11 observational cohort studies of general populations (106,195 persons total), the presence of frequent VPBs (defined as at least one VPB on a 10-second ECG or more than 30 in a one-hour recording) was associated with significantly higher risk of overall cardiac mortality (adjusted RR 2.1, 95% CI 1.7-2.5) and sudden cardiac death (adjusted RR 2.6, 95% CI 1.9-3.6). However, patients in these studies were not screened for underlying heart disease, which may have increased the apparent risk compared with other low-risk populations.

●In a cohort study of 5778 subjects, followed for 10 years, a VPB frequency >12 beats per day was an independent predictor for all mortality (hazard ratio [HR] 1.4), cardiovascular hospitalization (HR 1.1), all-cause hospitalization (HR 1.1), and new-onset heart failure (HF; HR 1.41).

VPB의 빈도는 예후에 영향을 줄 수 있습니다.  24-hour ambulatory ECG (Holter) 모니터링을 받은 Cardiovascular Health Study의 심장 질환이 없는 1139 명의 환자를 13년(중간값) 동안 추적 관찰한 결과, VPB 상위 1/4에 해당하는 환자(총 심박수의  0.123 % 이상)sms LVEF(OR 3.1, 95 % CI 1.4-6.8) 또는 HF (OR 1.5, 95 % CI 1.1-2.0) 발생과 의미 있게 더 관련되어 있었으며 all-cause mortality 가능성도 더 높았습니다(OR 1.3, 95 % CI 1.1-14.9).


명백하게 정상 심장을 가진 환자에서 frequent and complex ventricular ectopy의 예후적 의미에 대해서는 상충된 자료들이 있습니다.

● In one cohort of 73 asymptomatic healthy patients with frequent and complex ventricular ectopy identified on 24-hour Holter monitoring (including multiform VPBs, ventricular couplets, and ventricular tachycardia [VT]), outcomes after a 6.5-year follow-up were similar to those in the general population. Earlier studies also noted a favorable long-term prognosis in similar patients.

● In contrast, analyses of patients from the Multiple Risk Factor Intervention Trial (MRFIT), a study of apparently healthy persons aged 55 years or older and the Framingham Heart Study, have all shown a higher risk of mortality in patients with frequent or complex VPBs.

VPB polymorphism은 adverse outcomes를 예측하는 데 중요한 역할을 합니다. 평균적으로 10 년 동안 추적 관찰된 분명하게 정상 심장을 가진 대만인 3351 명의 연구에서 multiform VPBs 환자들(나이가 많고 이환율이 높은 환자)은 VPB가 없는 군에 비해 사망률(HR 1.6, 95 % CI 1.3-2.0), 입원률(HR 1.2, 95 % CI 1.1-1.4), new-onset HF(HR 1.5, 95 % CI 1.1-2.0) 및 new-onset atrial fibrillation(HR 1.5, 95 % CI 1.1- 2.3) 발생률이 증가하였습니다. Multiform VPBs 환자는 uniform VPBs 환자와 비교하여 사망률(HR 1.2, 95 % CI 1.0-1.5)과 all cause-hospitalization(HR 1.1, 95 % CI 1.0-1.3)이 높았습니다.

임신 결과에 빈번한 VPBs가 미치는 영향은 VPB burden이 1 %를 초과하고 구조적으로 정상 심장인 49 명의 여성의 53 건의 임신에서 조사되었습니다. Adverse maternal event rate는 11 %(HF  1 건, sustained VT 5 건)가 관찰되었으며 모든 사건들은 medical therapy로 성공적으로 관리되었습니다. Adverse event가 있는 모든 여성은 모두VPB burden이 5 %를 초과했습니다. VPB 그룹의 adverse fetal events  비율은 VPB가 없는 53 명의 임신부 정상 대조군과 유사하였습니다.

REF. UpToDate 2018.05.16