Percutaneous balloon aortic valvuloplasty: Results in 23 patients

CONGENITAL HEART DISEASE

Percutaneous Balloon Aortic Valvuloplasty: Results in 23 Patients ZUHDI LABABIDI,

MD, JIUNN-REN WU, MD, and JOSEPH T. WALLS, MD

Percutaneous balloon aortic valvuloplasty (BAV) was performed in 23 consecutive patients with valvular aortic stenosis with no associated cardiac defects. The patients were 2 to 17 years old and were referred from 12 hospitals in 4 states. The balloon was positioned across the aortic valve and inflated to pressures of 80, 100, then 120 psi. Each inflation lasted 5 to 10 seconds. The arterial and venous catheters were connected together outside the groin to avoid excessive increase in left ventricular pressure during total aortic valve occlusion with the inflated balloon. Peak systolic aortic valve pressure gradient and cardiac output were measured before and 15 minutes after BAV. There was no significant change in cardiac output, but all patients had a lessened gradient. The gradient before

BAV was 113 f 48 mm Hg, decreasing to 32 f 15 mm Hg after BAV (p
Transluminal balloon angioplasty is increasingly accepted as a nonsurgical technique for dilating stenotic arteries in the peripheral, renal and coronary circulations.1-4 The recent success of transluminal balloon coronary angioplasty in adults has prompted us and others to apply this principle to children with coarctation of the aorta, pulmonary arterial and valvular pulmanic stenosis.5-7 Application of balloon dilatation technique has not been previously described in patients with valvular aortic stenosis (AS). This report describes our experience with the first 23 consecutive patients with congenital AS who underwent percutaneous balloon aortic valvuloplasty (BAV).

17 years old at the time of BAV and were referred from 12 hospitals in 4 states. All patients had only AS with no associated cardiac defects. The mean resting peak systolic aortic valve pressure gradient (psg) for the entire group was 113 f 48 mm Hg (Table I). All patients were premeditated with 0.1 ml/kg body weight of lytic solution (each 1 ml containing 25 mg of meperidine, 6.25 mg of clorpromazine and 6.25 mg of promethazine) with a maximum of 2 ml given intramuscularly 30 minutes before the procedure. Percutaneous right- and left-sided cardiac catheterizations were performed through the right groin. Cardiac output was measured by the Fick principle using the LaFarge-Miettinen tables of assumed oxygen consumptions Pressure measurements were performed through fluid-filled catheters connected to Gould-Statham P23ID pressure transducers and Hewlett Packard 8805 C pressure amplifiers. A pullback pressure recording across the aortic valve was performed, followed by left ventricular (LV) and aortic root cineangiograms in the left anterior oblique view. The arterial catheter was then replaced by a double-lumen No. 9Fr balloon catheter (Meditech), which was introduced percutaneously over a flexible-tip 0.035-inch guide wire. All balloons used were 40 mm long. We attempted insertion of shorter balloons in patients with pulmonary valvuloplasty, but we found them ineffective because the shorter balloon tended to migrate above or below the valve opening when inflated.” The maximal inflatable diameters of the balloons were 10 to 20 mm-at least 1 mm smaller than the diameter of the aortic valve anulus as measured on the cineangiogram monitor.

Methods From October 1982 to July 1983, 23 consecutive patients who were thought to have moderate or severe AS, diagnosed by auscultation, electrocardiography, pulsed Doppler and 2-dimensional echocardiography, underwent cardiac catheterization, cineangiography and BAV. The patients were 2 to From the University of Missouri, Department of Pediatric Cardiology, Hospital and Clinics, Columbia, Missouri. Manuscript received August 3, 1983; revised manuscript received September 22, 1983, accepted September 26, 1983. Address for reprints: Zuhdi Lababidi, MD, Pediatric Cardiology, University of Missouri, Hospital and Clinics, One Hospital Drive, Columbia, Missouri 65212. 194

January 1, 1984

TABLE I

Hemodynamic

THE AMERICAN

Age (yr)

Aorta (mmHg)

t 10

115184 84163 78154 100175 115140 112167 92156 100/52 99170 118172 115164 101/67 160172 100/67 120186 86146 101/52 107/72 138199 115175 106168 73150 87749

9 f5

220110 f54/6

105165 f19/14

a 12 12 3 1:

1;' 1: 14

Mean fSD

LV (mmHg) 200/a 161/12 240/10 230/a 16515 27014 16516 15514 17014 18013 300/a 320/20 27018 210/20 192120 190122 21215 330/16 284115 199110 26417 170112 180/a

1; ; 19

195

Volume 53

Data Before and Soon After Balloon Aortic Valvuloplasty AfterValvuloplasty

Before Valvuloplasty Case No.

JOURNAL OF CARDIOLOGY

Psg (mmHg) a5 77 162 130 50 158 :I ;: 135 219 110 110 72 104 132 223 146

f48

Cl (I/min/m2)

(mmHg)

5.8 5.6 4.8 4.4 3.7 3.6 5.7 4.8 3.4 4.2 3.7 3.3 3.9 5.1 3.8 4.6 4.4 3.9 4.1 3.6 3.4 3.8 3.3

13519 125/10 180/20 15018 14517 14615 13017 12514 13014 15513 170/5 155/15 152/a 145/20 140122 164/20 138117 170123 215120 151/10 150/g 134110 124/10

107175 95168 100175 125183 126150 115175 102164 108172 lOOl68 135188 135185 110/74 130/96 120187 105/75 130187 122177 135153 i5o/aa 120185 110/72 108/80 113773

26 11

149112' f21/6

117176 f14/11

32' fl5

4.2 f0.7

LV

Aorta (mmHg)

Psg (mmHg)

29 40

Cl (I/min/m*) 6.2 5.3 4.7 4.6 4.0 3.7 4.9 4.5 3.9 3.8 4.0 4.3 4.1 4.8 4.2 5.0 4.5 4.1 5.6 4.2 4.3 4.0 3.5 4.4 --f0.6

* p
To avoid air embolization in the event of balloon rupture, we inflated and deflated the balloon several times outside the patient with a 50/50 mixture of saline solution and contrast medium until all air bubbles were removed. The balloon was also inflated and deflated once in the ascending aorta to make sure that it was not larger than the valve anulus. When the balloon catheter was introduced into the left ventricle over the guide wire, the middle of the balloon was positioned fluoroseopically across the aortic valve. The valve position had been visualized during aortic root cineangiography and marked on the monitor screen. At this point, the No. 9Fr balloon arterial catheter and the 7Fr venous catheter were disconnected from their strain-gauges and connected together using a Y-shaped metal connector with a syringe on the third end (Fig. 1). The balloon catheter was then sequentially inflated to pressures of 80,100 and 120 psi. Each inflation lasted 5 to 10 seconds. After each inflation the balloon was deflated and remained so for 2 to 3 minutes before reinflation. The balloon catheter was then replaced by the previous arterial catheter. Cardiac output and psg were measured again approximately 15 minutes after BAV, when the heart rate and aortic pressure had returned to pre-valvuloplasty levels. A second aortic root cineangiogram was performed in the left anterior oblique view. All aortic root cineangiograms were performed with a No. 7Fr multipurpose catheter with end and side holes, with the tip about 1 cm above the aortic valve. The arterial and venous catheters were then removed and a pressure bandage applied overnight. All patients were discharged t,he next morning and return visits were arranged. Results All 23 patients had moderate or severe AS with a resting psg of 50 to 223 mm Hg. With use of Hunt et al criteriatO for assessing aortic regurgitation, mild aortic regurgitation (grade l-2/5) was demonstrated with

aortic root cineangiography in 6 patients. No BAV was cancelled for technical reasons. All patients had an improved psg after BAV. The psg before valvuloplasty for the entire group was 113 f 48 mm Hg, and it decreased to 32 f 15 mm Hg after BAV (p
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PERCUTANEOUS BALLOON

TABLE II

AORTIC VALVULOPLASTY

Hemodynamic Data of 6 Patients Soon After Balloon Aortic Valvuloplasty and at Follow-up After Valvuloplasty

Follow-Up

Follow-Up

Period (mo)

Mean fSD Abbreviations

Aorta (m:Hg)

(mm Hg)

13.519 180120 13017 155115 138117 124110

107/75 100175 102f64 110174 122177 113173

144/l 1 f21/5

109173 f8/5

Aorta

Psg (mm Hg)

Cl (I/min/m2)

f:

6.2 4.7 4.9 4.3 4.5 3.5

148110 180/18 12518 184112 117/12 14017

126167 89141 105165 122170 102770 125/90

4.7 0.1

149111 f28/4

111167 f15/16

f

!

::

*Z

(m:Hg)

(mm Hg)

Psg (mm Hg) ;: ;s :z

*3382

(I/mkm2) 6.1 5.0 5.1 5.6 4.6 4.3 5.1 fO.l

as in Table I.

were bicuspid with small tears measuring 1 to 4 mm on the free ends of the aortic commissures. Six patients have had repeat cardiac catheterizations 3 to 9 months after BAV. In each of the 6 patients there was no significant change in psg or cardiac output between the study immediately after valvuloplasty and the 3 to 9 month follow-up, indicating persistence of the dilatation (Table II). Discussion

FIGURE 1. The left ventricular-right atrial shunt when the inflated balloon occludes the aortic valve orifice. The arterial and venous catheters are connected together using a Y-shaped metal connector.

bolization or ill effects. Inspection of the ruptured balloons after the procedure showed a clean-cut lengthwise tear in each balloon. On discharge and during the I- to g-month follow-up period, the femoral pulses remained normal and equal with no evidence of arterial or venous compromise to the legs. Although there was significant improvement in the psg in all patients, psg after valvuloplasty was still moderately severe in 2 patients (65 and 80 mm Hg). Both underwent open aortic commissurotomy using extracorporeal circulation which provided an opportunity to observe the mechanism of balloon valvuloplasty. At operation, both aortic valves

Congenital AS is a common congenital cardiac defect, comprising 3 to 6% of all congenital heart diseases.rl Although open aortic valvulotomy is well established with a low surgical mortality, it is still regarded as palliative because most patients require reoperation.i2 Percutaneous transluminal balloon angioplasty has been helpful in certain coronary and peripheral vascular diseases and seems to be promising in treating valvular aortic and pulmonary stenosis. During pulmonary balloon valvuloplasty, the large and stiff balloon catheter may render the tricuspid valve insufficient, thus preventing the right ventricular pressure from rising too high when the balloon totally occludes the pulmonary valve. Because the catheter does not pass through the mitral valve during aortic valvuloplasty, the arterial and venous catheters were connected together outside the body in order to create a LV-right atrial shunt to prevent the LV pressure from increasing too much when the balloon totally occludes the aortic valve. The potential benefits of this are entirely speculative. Success in increasing the diameter of the aortic valve opening depended a great deal on a high intraballoon pressure. At 80 psi, the balloon inflated only to an hourglass shape. At 100 to 120 psi, the balloon became cylindrical in shape, indicating that the valve had been opened or stretched to the full diameter of the balloon. This high pressure requirement also was demonstrated in vitro on excised coarctation specimens by Lock et al.‘” To avoid a false change in psg, the pressure measurements after BAV were performed when the heart rates and cardiac outputs were approximately equal to values before valvuloplasty. Although the exact effect is not known, and the hypothesis was not supported,

January 1, 1984

using the LV-right atria1 catheter shunt outside the groin may have decreased the myocardial or mitral apparatus insult when the aortic valve was totally occluded. The mechanism of relief of the obstruction seems to be a stretching of the valve leaflets and minor tearing of the aortic commissures (as demonstrated in 2 patients). According to Lock et al,lJJs in coarctation of the aorta and pulmonary arterial stenosis the dilating effect seems to be a tearing of the intimal and medial layers of the artery. BAV may be an alternative method of treating AS. The advantages are that it is less expensive than open commissurotomy, does not involve sternotomy and requires only 2 days of hospitalization. Because it does not involve the use of blood, it may be helpful in treating children whose parents object to the use of blood on religious grounds. References 1. Dotter CT, Judkins MP. Transluminal treatment of arteriosclerotic obstruction: description of a new technique and a preliminary report of its application. Circulation 1964;30:654-670. 2. Gruntzia AR. Sennina A. Sieaenthaler WE. Nonooerative dilatation of coronary artery stenosis:‘perc?aneous transluminal angioplasty. N Engl J Medl979;301:61-68.

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3. Tegtmeyer CJ, Dyer R, Teates CD, Ayers CR, Carey RM, Wellons HA, Stanton LW. Percutaneous transluminal dilatation of the renal arteries: techniques and results. Radiology 1980; 135589-599. 4. Spence RK, Freiman DB, Gratenby R, Hobbs CL, Barker CF, Berkowitz HD, Roberts B, F&Cleans G, Oleaga J, Ring EJ. Long-term results of transluminal angioplasty of the iliac and femoral arteries. Arch Surg 1981;116:1377-1386. 5. Singer MI, Rowen R, Oorsey TJ. Transluminal aortic balloon angioplasty for coarctation of the aorta in the newborn. Am Heart J 1982;103:131132. 6. Kan JS, White RI. Mitchell SE. Gardner TJ. Percutaneous balloon valvuloplasty: a new method for treating congenital pulmonary valve stenosis. N Enol J Med 1982:370:540-543. 7. Lock‘;lE, Nieml T,-Enzig S, Amplatz K, Burke BA, Bass JL. Transvenous angioplasty of experimental branch pulmonary artery stenosis rn newborn lambs. Circulation 1981;64:886-692. a. LaFarge CG, Mlettinen OS. The estimation of oxygen consumption. Cardiovasc Res 1970;4:23-30. 9. Lababidi 2, Wu JR. Percutaneous balloon pulmonary valvuloplasty. Am J Cardiol 1982;52:560-563. 10. Hunt D, Baxley WA, Kennedy JW, Judge TP, Williams JE, Dodge HT. Ouantitative evaluation of cineaortography in the assessment of aortic regurgitation. Am J Cardiol 1973;31:696-700. 11. Friedman WF, Benson LN. Aortic stenosis in heart disease in infants, children and adolescents. 3rd ed. In: Adams FH. Emmanonilides GC, eds. Baltimore: Williams 8 Wilkins, 1983:171. 12. Presbitio P, Somerville J, Revel-Chion R, Donald R. Open aortic valvulotomy for congenital aortic stenosis-late results. Br Heart J 1982;47: 26-34. 13. Lock JE, Castaneda-Zuniga WR, Bass JL, Foker JE, Amplatz K, Anderson RW. Balloon dilatation of excised aortic coarctations. Radiology 1982; 143:689-691. 14. Lock JE, Niemi T, Burke BA, Einzig S, Castaneda-Zuniga WR. Transcutaneous angioplasty of experimental aortic coarctation. Circulation 1982;66:1280-1285. 15. Lock JE, Castaneda-Zuniga WR, Fuhrman BP, Bass JL. Balloon dilatation angioplasty of hypoplastic and stenotic pulmonary arteries, Circulation 1983;67:962-967.