Warnecke H, Müller J, Cohnert T, Hummel M, Spiegelsberger S, Siniawski H K, Lieback E, Hetzer R
German Heart Institute, Berlin.
J Heart Lung Transplant. 1992 Nov-Dec;11(6):1093-102.
In a prospective clinical study, routine endomyocardial biopsy (EMB) for early detection of cardiac allograft rejection was replaced by two noninvasive diagnostic techniques. In 32 patients who underwent transplantation during a 6-month period, intramyocardial electrogram (IMEG) amplitude was recorded with the telemetry function of a dual-chamber pacemaker system. An amplitude decrease of more than 8% below the individual range of variability in overnight long-term recordings served as an indicator of rejection. A prolongation of the time interval Te--the time span between maximal posterior wall contraction and peak retraction velocity--of more than 20 msec was used as an additional indicator of rejection-related left ventricular dysfunction. For patient safety, routine EMBs were still performed but remained undisclosed to the transplantation team. The pathologist was asked to intervene in cases of discrepancies between biopsy results and medical decisions, but no such intervention was necessary. Twenty-seven rejection episodes were treated medically, of which 22 were diagnosed noninvasively. In four patients, EMB, ordered because noninvasive parameters remained inconclusive, led to medical treatment. No false negative IMEG results were observed. Retrospective correlation with rejection gave a 100% negative predictive value for IMEG and a 96.9% negative predictive value for echocardiographic diagnosis. We conclude that omission of a schedule of routine biopsies is justified, if the described techniques of IMEG and echocardiography are meticulously applied and indicate normal cardiac function. EMB remains indicated if noninvasive parameters are not conclusive or if false-positive IMEG results, which were observed in the presence of infection or arrhythmias, are suspected. The frequency of EMB can be reduced by 90%, compared to conventional routine biopsy schedules. Diagnostic safety is increased because the additional information gained from IMEG and echocardiography is helpful in the interpretation of EMBs.
在一项前瞻性临床研究中，用于早期检测心脏移植排斥反应的常规心内膜心肌活检（EMB）被两种非侵入性诊断技术所取代。在6个月期间接受移植的32例患者中，利用双腔起搏器系统的遥测功能记录心肌电图（IMEG）振幅。夜间长期记录中振幅下降超过个体变异范围的8%被用作排斥反应的指标。后壁最大收缩与峰值回缩速度之间的时间间隔Te延长超过20毫秒被用作排斥反应相关左心室功能障碍的附加指标。为了患者安全，仍进行常规EMB，但结果不对移植团队公开。要求病理学家在活检结果与医疗决策存在差异的情况下进行干预，但并无此必要。27例排斥反应发作采用药物治疗，其中22例通过非侵入性诊断。在4例患者中，因非侵入性参数仍不明确而进行的EMB导致了药物治疗。未观察到IMEG结果为假阴性的情况。与排斥反应的回顾性相关性显示，IMEG的阴性预测值为100%，超声心动图诊断的阴性预测值为96.9%。我们得出结论，如果精心应用所述的IMEG和超声心动图技术且显示心脏功能正常，那么省略常规活检计划是合理的。如果非侵入性参数不明确，或者怀疑存在感染或心律失常时出现IMEG假阳性结果，则仍需进行EMB。与传统的常规活检计划相比，EMB的频率可降低90%。由于从IMEG和超声心动图获得的额外信息有助于解释EMB结果，因此诊断安全性提高。
