CORRESPONDENCE

To THE EDITOR:

The opinions stated in a recent editorial [l] should not go unchallenged. T o say that very few patients with acquired valvular disease need to undergo cardiac catheterization is at its best a gross oversimplification. The stethoscope, chest x-ray, and electrocardiogram remain valuable diagnostic aids. In recent years, however, it has been well established that their value is limited and that cardiac catheterization can most often supplement them to the advantage of the patient.

According to most authorities [4, 91, the patient with a small aortic leak presents no peripheral vascular signs or only slight alteration in pulse pressure; on the other hand, the patient with a large leak causing “free aortic regurgita- tion” displays several distinctive peripheral vascular signs: low diastolic and high pulse pressures, Corrigan’s pulse, visible arterial pulsations, “pistol shot” sound over the femoral artery, Duroziez’s sign, and capillary pulse. There are, however, patients with marked aortic regurgitation but without these classic peripheral vascular signs [5]. Cineaortography is the only technique affording a more accu- rate assessment of the degree of regurgitation. Deterioration of these patients progresses very rapidly, once decompensation has taken place; thus, each case of aortic insufficiency deserves a complete evaluation, including cineaortography. Cineaortography has demonstrated the presence of moderate aortic regurgitation in some patients with mitral stenosis, aortic stenosis, or a combination of mitral stenosis and insufficiency but without the diastolic murmur of aortic insuffi- ciency [81. This has been called silent rheumatic aortic regurgitation.

The results following insertion of a mitral prosthesis are still less satisfactory than in the aortic area. For this reason, a stenotic mitral valve should be excised only when it is impossible to perform a satisfactory open commissurotomy. It is possible to predict the feasibility of an adequate mitral commissurotomy by cineangiography [Z]. An area of negative contrast or a pseudo-filling defect ap- pearing in the left ventricular outflow tract at the end of left ventricular diastole but absent during the remainder of the cardiac cycle indicates the presence of a stenotic but soft and pliable mitral valve easily amenable to surgery. Its absence indicates that the valve is not only stenotic but has become so rigid that a satis- factory commissurotomy (by the open-heart technique) cannot be done.

Confusion between rheumatic mitral disease and primary myocardial disease is sometimes very difficult to avoid [51. Mitral pansystolic murmurs are common in the latter, and diastolic rumbles are by no means rare. Furthermore, atrial fibrillation is a frequent complication of both conditions. In the absence of a definite history of rheumatic fever, the differential diagnosis can be next to impossible.

Cardiac catheterization can be of help in proving the existence of a diastolic gradient between the left atrium and the left ventricle when mitral stenosis is the cause of the patient’s symptoms; likewise, the absence of such a gradient in the case of primary myocardial disease can also be determined. Unnecessary op- erations can thus be easily avoided.

It is our opinion that a male patient with a history of angina pectoris and

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an ejection-type systolic murmur compatible with aortic stenosis deserves cardiac catheterization and coronary cinearteriography as well.

I t is not rare to find a peak systolic gradient of only 20 to 30 mm. Hg across the aortic valve, while the major coronary trunks are severely narrowed in several spots. To replace the aortic valve of such a patient with a prosthesis (with a systolic gradient of 10 to 20 mm. Hg) does not seem to be a very profitable operation, even if the patient were able to survive it.

A most important contribution of cardiac catheterization has been the evalu- ation of the results of cardiac surgery. Kay et al. [61 compared the pulmonary artery pressures at rest and during exercise of patients with closed or open mitral commissurotomy. Eighty-four percent of the patients operated upon with the open technique had normal pulmonary artery pressures at rest, as against only 64% of the patients operated upon by the closed technique. Following exercise, the pulmonary artery pressure remained below 50 mm. Hg in only 28% of the closed surgery group, in contrast to 78% below 50 mm. Hg in the open surgery group.

Cardiac catheterization is at the present time the most accurate way to evaluate the results of several types of surgery available for the correction of valvular diseases. Morrow et al. 171 have used cardiac catheterization to assess their surgical results in congenital aortic stenosis. They found that hemodynamic improvement in patients with the highest preoperative gradients was not so satisfactory as in those with less severe stenosis.

Left heart catheterization is the most accurate method to measure the severity of aortic stenosis. No less than 25% of patients with severe aortic stenosis (systolic gradient over 50 mm. Hg) have a normal electrocardiogram or a tracing in which left ventricular hypertrophy can be diagnosed only by voltage criteria, which is a most unreliable method. On the other hand, 10% of the patients with aortic stenosis have only a slight aortic gradient in the presence of electrocardiography criteria of left ventricular hypertrophy. Thus, the electrocardiographic changes do not always correlate sufficiently closely with the hemodynamic evidence of obstruction to the left ventricular outflow to allow accurate evaluation of its severity.

These are only a few problems which we firmly believe cardiac catheteriza- tion can help elucidate. The list could be made much longer, but a complete discussion on this subject would go beyond the goal of this letter, which is to show that cardiac catheterization has a definite place in the evaluation of all patients with acquired valvular disease as well as in patients with congenital heart disease.

The more completely the patient is studied, the better prepared is the surgeon to do his best with the most possible benefit occurring to the patient; hence, “To measure is to know.”

HENRY A. ZIMMERMAN, M.D. MA~TIAL DEMANY, M.D. St. Vincent Charity Hospital

Cleveland

REFERENCES

1. Ankeney, J . L. Use and abuse of cardiac catheterization. A n n . Thorac. Surg. 5:660, 1965.

2. Demany, M. A., Kay, E. B., and Zimmerman, H. A. An angiographic sign for the evaluation of the stenotic mitral valve. Unpublished observations.

3. Demany, M. A., and Zimmerman, H. A. Marked aortic regurgitation without peripheral vascular signs. Dis. Chest 49:61, 1966.

4. Friedberg, C. K. Diseases of the Heart (2d ed.). Philadelphia: Saunders, 1956.

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5. Harvey, W. P., Segal, J. P., and Gurel, I. The clinical spectrum of primary myocardial disease. Progr. Cardiov. Dis. 7: 17, 1964.

6. Kay, E. B., Rodriguez, I?., Haghighi, D., Suzuki, A., and Zimmerman, H. A. Mitral stenosis: Comparative analysis of postoperative results following the closed and open operative approach. Amer. J . Cardiol. 14:139, 1964.

7. Morrow, A. G., Goldblatt, A,, and Braunwald, E. Congenital aortic stenosis: 11. Surgical treatment and the results of operation. Circulation 27:450, 1963.

8. Segal, B. L., Likoff, W., and Kaspar, A. I. “Silent” rheumatic aortic regurgi- tation. Amer. J . Cardiol. 14:628, 1964.

9. Wood, P. Diseases of the Heart and Circulation (2d ed.). Philadelphia: Lip- pincott, 1956.

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