Is Fluoroscopy Necessary for Pacemaker Insertions and His Bundle Studies?

To the Editor: The findings of our study have clearly demonstrated that prudent medical intervention is capable of improving markedly the quality of life in patients with severe angina pectoris. Contrary to the conclusion drawn by Major Procacci, however, the data also strongly suggest that life expectancy in these patients may be favorably influenced by optimal therapy. While it is true that the annual attrition rate in the 133 "treated" patients in our series was similar to that reported for "untreated" patients in the Framingham study, there was a significant difference in the clinical profiles of thesubjects comprising the respective series. The Framingham group included patients with unclassified angina pectoris of all degrees of frequency and severity; our study was limited to patients with disabling angina pectoris unresponsive to conventional modes of therapy. In the Framingham survey, patients were included in whom angina developed along with or following a first myocardial infarction; our series comprised a similar percentage of cases with prior infarction but in almost half of these, two or more documented attacks had already occurred before entry into the study. Similarly, our "good risk" patients, for whom an annual mortality rate of only 1.2 percent was recorded, cannot be considered comparable with the "low risk" patients of the HIP series in which the "untreated" mortality was 1.8 percent per year. All of our "good risk" patients suffered from severe and refractory forms of angina pectoris and in more than one-third of their number the ECG was distinctly abnormal. In the HIP study, on the other hand, angina varied from mild to severe in different patients and selection was based on the presence of a normal ECG and blood pressure. Thus, despite the lower annual attrition rate found in our "good risk" patients, the expected mortality based on severity of disease should have appreciably exceeded that of the "low risk" patients in the HIP series. These findings would seem to emphasize the obligation of the practicing physician to utilize optimal medical care prior to consideration of surgery. Unfortunately, patients being referred for revascularization procedures today are often found to have had medical care no better, and often worse, than that which prevailed 100 years ago. In a recent survey of 200 patients admitted for bypass surgery allegedly for severe angina pectoris, 46 percent were found to have been treated with no other drug but nitroglycerin (unpublished data). Ineffectual agents had often been prescribed and potent drugs administered indiscriminately or improperly. Frequently little effort had been expended by patient or physician to eliminate either the precipitating factors for angina pectoris or risk factors for atherosclerosis. In CHEST, 66: 5, NOVEMBER, 1974

not a single instance was the patient returned to the referring physician with the recommendation for more intensive medical management or was surgery deferred on this account. From such practices neither the attending physician nor the cardiovascular surgeon can hope to stand on firm ground in attempting to evaluate the indications or benefits of operative intervention. Henry 1. Bussek, M.D. Research Professor of Cardiovascular Disease, CliniCal Professor of Medicine, New York Medical College, New York, N.Y.

Is Fluoroscopy Necessary for Pacemaker Insertions and His Bundle Studies? To the Editor: The article by Kimbiris et aI, in the January, 1974 issue of Chest re-emphasizes an extremely important point, namely: right heart catheterization in patients with complete LBBB carries the potential for inducing transient complete heart block. I must, however, take exception to the authors' assertion that pacemaker insertions and His Bundle studies should never be performed without fluoroscopy in these patients. When these procedures are performed with balloon-tipped floating catheters inserted via the femoral vein, I.2 the first part of the catheter to enter the right ventricle is the tip, which carries pacing electrodes. Thus, in order for the catheter tip to contact and traumatize the right bundle branch, it must be within the right ventricle and in position to pace immediately if this becomes necessary. Primarily for this reason, but also because we have never observed development of RBBB in over 100 passages of Swan-Ganz catheters of all types, we doubt that the risk arising from this particular complication is appreciably greater than if the procedure were carried out with fluoroscopy. It is indeed conceivable that the risks could be less with floating catheters which are very soft and flexible and possibly less likely than semi-rigid conventional catheters to traumatize cardiac conduction tissues. Since the authors have provided no comparative data on this point, their sweeping conclusion seems unwarranted. Steven G. Meister, M.D., Philadelphia REFERENCES

1 Meister SC, Banka VS, Helfant RH: Transfemoral pacing with balloon-tipped catheters. JAMA 225:712,1973 2 Meister SC, Banka VS, Chadda KD, et al: A balloon tipped catheter for obtaining His bundle electrograms without Huoroscopy. Circulation 49:42,1974

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