Heart Vessels (1992) Suppl. 7: 146-153

Heart

andVesse~S

© Springer-Verlag1992

Percutaneous transluminal angioplasty in Takayasu arteritis M o h a m m e d Khalilullah and S a n j a y Tyagi Department of Cardiology, Govind Ballabh Pant Hospital, New Delhi - 110002, India

Summary. Percutaneous transluminal balloon angioplasty (PTBA) was performed in 87 patients for 111 stenotic lesions due to Takayasu arteritis. Of the lesions attempted for dilatation, 35 were in the aorta, 64 in renal arteries, 9 in subclavian, and 3 in common iliac arteries. The stenosis of aorta could be successfully dilated in 33 of 35 (94.3%) patients with fall in peak systolic pressure grädient (PSG) from 77.7 + 28.4mmHg to 26.4 + 20.6mmHg (P < 0.001) and increase in luminal diameter from 4.7 + 2.4mm to 10.1 + 4.1mm (P < 0.001). On hemodynamic and angiographic restudy in 20 patients at 3-24 months (mean 7.7 + 4.1 months) further fall in PSG (t>15 mmHg) was observed in 7 patients, no significant change in 12 patients and restenosis with increase in PSG in one patient which could be successfully redilated. Late restudy at 36-60 months (mean 43 + 9.4) in six patients showed continued relief of stenosis (mean PSG 8.8 + 7.8mmHg). Of the 64 stenotic lesions of the renal arteries, 58 (90.6%) could be successfully dilated with decrease in stenosis from 89.1 + 10.1% to 29.9 + 14.9% (P < 0.001). Follow-up intra-arterial digital subtraction angiography in 25 patients at a mean follow-up period of 13.1 months (range 3-29 months) showed restenosis in 5/36 (13.9%) lesions which could be successfully redilated. Angioplasty was also successful in dilating 8/9 (88.9%) subclavian and all 3 common iliac artery stenosis. There was marked improvement in symptoms after successful angioplasty. Blood pressure was reduced to normal or improved in all successfully dilated aortic stenosis and in 84.6% of renal artery stenosis. In conclusion, PTBA is safe, highly effective, and therelore should be considered as the treatment of choice particularly for discrete stenotic lesions due to Takayasu arteritis.

Address correspondence to: M. Khalilullah

Key words: Aorta, d i s e a s e s - Aorta, s t e n o s i s Hypertension - Percutaneous transluminal angioplasty - Renäl artery, stenosis - Subclavian artery, stenosis

Introduction Takayasu arteritis is an inflammat0ry disease involving the aorta, its rriajor branches and pulmonary arteries, leading to stenotic lesions in the affected vessels. Morbidity and mortality in this disease are due to severe hypertension, congestive heart failure and organ ischemia [1]. In the absence of knowledge of a specific etiology, medical therapy has been empiricial, with little effect once the disease has reached its chronic stage. Surgical therapy has been used, but multifocal involvement and dense transmural fibrosis make surgery difficutt. Reconstructive procedures have significant morbidity, mortality and post-operative complications [2, 3]. Experience with percutaneous transluminal balloon angioplasty (PTBA) of stenotic lesions in Takayasu arteritis is limited [4-14] and long-term follow up studies are not available. Since our initial success with balloon dilatation of the aorta in aortoarteritis [15] we have attempted balloon dilatation of stenotic arterial lesions in 87 patients with Takayasu arteritis. Here we report our initial and follow up results of PTA of stenotic vascular lesions in Takayasu arteritis.

Methods Between January, 1986 and May, 1991, 87 patients, 22 male and 65 females, aged 5-36 years (mean 18.7 + 7.6 years) were treated with PTBA. Of the 111 lesions attempted 35 were in the aorta, 64 in renal arteries, 9 in subclavian and 3 in common iliac arteries. The diagnosis of Takayasu arteritis was based on clinical, laboratory and arteriographic findings as established by Aortitis syndrome research committee of

M. Khalilullah and S. Tyagi: Percutaneous transluminal angioplasty Japan [16]. Erythrocyte sedimentation rate was normal in 83 patients and mildly elevated in 4. All the patients were subjected to cardiac catheterization and cine/digital subtraction angiography. Examination was performed under general anaesthesia in children and local anaesthesia in adults. Morphine was used for sedation and analgesia during angioplasty in the later group. All patients were routinely started on aspirin (300mg/day) and dipyridamole (300 mg/day) 2 days before the procedure which was continued after the angioplasty.

Angioplasty of the aorta Thirty-five patients with Takayasu arteritis underwent PTBA for stenosis of aorta. The main presenting symptom was dyspnea on exertion in 29 patients and claudication in 5 patients. One patient presented with hypertensive encephalopathy. On examination, all patients had very feeble or impalpable lower limb pulsations with variable combination of reduced or normal upper limb and carotid pulsations. Thirty-one patients were hypertensive while four were in N Y H A class IV due to severe congestive cardiac failure but had no associated hypertension or valvular regurgitation. Cardiac catheterisation, aortography and angioplasty were performed using previously described technique [15]. The balloon size was 60% to 100% of the normal aortic segment but did not exceed three times the constricted segment. The balloon (Meditech Inc., Mass, USA) mounted on 5 F - 9 F catheter were 7-20 mm in diameter and 2 - 4 cm long. After positioning the balloon across the stenotic segment, the balloon was inflated 2 - 4 times, for 15-30 each, with diluted contrast, sequentially to higher pressure, until the "waist" on the balloon disappeared or the maximum inflation pressure limit of the balloon was reached. Aortic pressure below the stenosis was continuously monitored through a pigtail catheter inserted through the opposite femoral artery. After angioplasty, aortography was performed in the same views and when the heart rate was near the predilatation level, the pressure pull-back tracing was recorded. Procedures resulting in an increase in diameter of stenosed aorta by more than 30% and a fall in a gradient to less than one-half of that before dilatation were considered successful [17]. All patients have been followed-up clinically. Twenty patients have undergone restudy by cardiac catheterisation and aortography at 3-24 (mean 7.7 + 4.1) months after balloon angioplasty. Six patients have undergone late (at 36-60, mean 43 + 9.4 months) follow-up recatheterisation and aortography.

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formed followed by selective catheterisation and angiography of the stenosed artery to localize the site and severity of the stenosis. For choosing the balloon size, the vessel was measured proximal and distal to the stenosis and the original size of the vessel was estimated in the area of the stenosis. The diameter of the balloon selected was equal to the estimated diameter of the artery in the stenosed area. The balloon was gradually inflated with diluted contrast medium using a 10tal syringe with pressure gauze until the "waist" on the balloon produced by the stenosis disappeared or the maximum inflation pressure limit of the balloon was reached. Intra-arterial heparin (3,000-5,000 units) was administered during the procedure and continued for 2 days after angioplasty. Aspirin (300mg/day) and dipyridamole (300mg/day) started 2 days before the procedure were continued for the following 6 months.

Renal angioplasty Balloon angioplasty for renal artery stenosis was attempted in 48 patients for 64 lesions with more than 75% luminal diameter narrowing. All patients had moderate to severe hypertension, poorly controlled with two or more antihypertensive medications. Renal angioplasty was performed through the femoral artery in 43 patients and through a high brachial approach due to the sharp caudal angle of the renal artery in five patients. In all patients, angioplasty was performed using the two-step catheter exchange technique described by Tegtmeyer [18]. In patients with bilateral renal artery stenosis, initially the artery with the most significant stenosis was dilated. Abdominal aortography was done to evaluate the success of the procedure. If the result of the first dilatation was satisfactory, we then dilated the contralateral renal artery and evaluated the results on an aortogram. The procedure was considered to be technically successful if the residual stenosis was 50% or less on the post dilatation angiogram. Clinical results of P T R A were evaluated according to the blood pressure response after angioplasty [19]. If the diastolic pressure was 90mmHg or less in the absence of antihypertensive medications, patients were considered cured. If the decrease in diastolic pressure was at least 15% hut medication was still required, they were considered improved. If there was a smaller fall in pressure or no decrease at all, the procedure was regarded as having failed. Patients were followed up clinically. Follow-up restudy by catheterisation and angiography was performed in 25 patients at 3-29 (mean 13.1 + 6.4) months after angioplasty.

Angioplasty of the aortic branches

Subclavian angioplasty

For angioplasty of the aortic branches (renal, subclavian, and iliac) initially an aortogram was per-

Balloon angioplasty was performed in nine patients with more than 75% stenosis of the subclavian artery.

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M. Khalilullah and S. Tyagi: Percutaneous transluminal angioplasty

Eight patients presented with arm claudication and one with subclavian steal syndrome. Initially arch aortography was performed to determine the extent of occlusive disease in arch vessels. Selective catheterization of the subclavian artery was performed via femoral approach. Subclavian angiography was performed to localize the site and origin of vertebral artery and its position was marked on the skin with radiopaque markers. The stenosis was crossed with 0.035-inch straight, floppy tipped guide wire, followed by a 5 French diagnostic catheter and the guide wire was withdrawn. The intraluminal position of the catheter was verified and heparin was administered intra-arterially through the catheter distal to the stenosis and the catheter was withdrawn. The Balloon catheter was passed over the exchange guide wire, positioned across the stenosis and inflated for 1015 s, from 2 to 4 times.

Table 1. Hemodynamic and angiographic findings in 35 patients with aortic angioplasty

PSG (mmHg) Diameter of aorta at site of stenosis (mm)

Before PTBA Mean + SD (range)

After PTBA Mean + SD (range)

p Value

77.7 + 28.4 (30-135) 4.7 + 2.4 (2.3-10.8)

26.4 + 20.6 (0-60) 10.1 + 4.1 (5-19.6)

15mmHg) was observed in 7 patients, no significant change in 12 patients and an increase in the PSG from 15 mmHg to 85mmHg was observed in one patient at 6 months after angioplasty. Restenosis of the aorta in this patient could be successfully redilated and she shows continued improvement 9 months after second angioplasty. Second-follow-up hemodynamic and angiographic restudy at 36 to 60 (mean 43 _+ 9.4) months after angioplasty performed in 6 patients showed no evidence of restenosis or aneurysm formation. Clinical results The femoral pulse, which had been either absent or very feeble, became palpable with increased pulse volume in all 33 successfully treated patients. On follow-up of 2-59 (mean 30.9 _+ 19.7) months, all these patients had marked improvement of their symptoms. Twenty-nine (87.8%) of the thirty-three successfully treated patients had systemic hypertension before angioplasty. Successful angioplasty was followed by fall in blood pressure in all patients, which occurred within 24-48h and was maintained thereafter. The average blood pressure decreased from 182/112 mmHg before angioplasty to 137/86 mmHg on follow-up after angioplasty. In nine patients with associated renal artery stenosis, residual hypertension further improved after successful renal angioplasty. Symptoms of claudication in five patients were markedly relieved. Four patients with severe congestive heart failure without associated hypertension or valvular regurgitation and normal ESR improved from NYHA Class IV to II after angioplasty.

Renal angioplasty Of the 48 patients undergoing angioplasty, renal artery stenosis was unilateral in 23, bilateral in 16, and 9 had renal artery stenosis of the solitary functioning kidney. Fifty-eight (90.6%) of the sixty-four stenotic lesions could be successfully dilated. Of the 6 (9.4%) failures, 4 were due to an inability to cross the lesion by guide wire/balloon catheter and 2 lesions were resistant to dilatation despite inflating the balloon up to 10atm. The degree of stenosis decreased from 89.1 _ 10.1% to 22.9 +_ 14.9% (P < 0.001) (Fig. 2). The balloon inflation pressure required for angioplasty was 7.9 +_ 2.3 atm (fange 4-17 atm). Patients complained of flank/abdominal pain during balloon inflation which disappeared on deflation. One patient developed intimal flap which was patched up by low pressure, long duration (5min) balloon inflation. A smal! pseduoaneurysm of the brachial artery developed in one patient and was corrected by minor surgical repair. There were no other complications.

Fig. 2a,b. Digital subtraction angiopraphy of the abdominal aorta showing a severe, discrete stenosis of left renal artery and severe diffuse stenosis of right renal artery before angioplasty, and b widening of lumen of right renal artery and complete relief of discrete stenosis of left renal artery

Follow-up intra-arterial digital subtraction angiography in 25 patients at a mean follow-up of 13.1 _+ 6.4 (fange 3-29) months after successful angioplasty for a total of 36 lesions showed restenosis in 5 (13.9%) lesions, all of which could be successfully redilated. Restenosis was associated with recurrence of hypertension which was relieved after successful redilatation. Successful angioplasty was usually followed by fall in blood pressure 24-48 h after angioplasty and further in the week following angioplasty. In some patients, blood pressure did not fall immediately after the procedure but improved gradually over the weeks following angioplasty. Thirty-nine patients with successful renal angioplasty have been followed up clinically. Evaluation at the last follow-up visit (fange

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M. Khalilullah and S. Tyagi: Percutaneous transluminal angioplasty streptokinase infusion. The upper limb pulsations became palpable and relief from symptoms was observed in eight successfully treated patients. On follow-up of 3-41 (mean 15.5 + 8.3) months in these eight patients, seven showed continued clinical improvement. One patient with poor distal flow due to occlusion of the axillary artery and elevated ESR had restenosis of the subclavian artery after 3 months which could be successfully reditated.

Iliac angioplasty

a

•

I

All 3 stenotic common iliac arteries could be successfully dilated with 75%-100% restoration of expected normal lumen diameter (Fig. 4). Femoral, popliteal, and tibial pulsation, which were not palpable, became clearly palpable. The prior severe claudication was also markedly relieved. On follow-up of 5-18 months, all patients continue to be asymptomatic with good volume pulsations in the leg arteries.

Discussion

Fig. 3a,b. Digital subtraction angiogram of left subclavian artery showing a severe, long segment stenosis of postvertebral artery segment before angioplasty, and b restoration of normal lumen after angioplasty

3-50, mean 19.4 + 10.3 months) showed that 33 out of 39 (84.6%) patients responded well to angioplasty. Hypertension was cured in 17 (43.6%) and improved in another 16 (41%) patients.

Subclavian angioplasty Of the nine patients subjected to subclavian angioplasty, one had stenosis proximal to the vertebral artery and eight had stenosis distal to the vertebral artery. Eight of the nine (88.9%) stenotic subclavian arteries could be successfully dilated with 75%-100% restoration of the expected normal lumen diameter (Fig. 3). Before the availability of high pressure balloons, subclavian artery stenosis in one patient could not be dilated despite using 6 atm for balloon inflation. The pressure required for balloon inflation ranged from 2-16 (mean 7.9 _+ 3.4) atm. The only complication was thrombosis at the angioplasty site in one patient, which could be successfully lysed by

Balloon angioplasty has been shown to be an effective mode of dilating coarctation of the aorta [20], postsurgical recoarctation [21], and atherosclerotic stenosis of aorta [22] and it's branches [23, 24]. The first successful angioplasty for Takayasu's arteritis was reported in 1980 by Martin et al. [4] for subclavian artery stenosis and by Saddekni et al. [5] for renal artery stenosis. Subsequently, Yagura et al. [7] (1984) and Khalilullah et al. [15] (1987) performed successful angioplasty of aortic stenosis. Since then, a few other small series [6, 8-14] of patients have appeared, describing encouraging initial results of balloon angioplasty for stenotic arterial lesions in Takayasu arteritis.

Balloon angioplasty of the aorta This study shows that balloon angioplasty is highly successful in relieving stenosis of aorta due to Takayasu's arteritis. Similar encouraging results have been reported by other investigators also (Table 2). Review of these data indicate that balloon angioplasty can be successfully performed to relieve aortic obstruction in the vast majority of patients. The procedure is highly effective for discrete stenotic lesions. Long segment aortic stenosis should also be initially attempted for with balloon angioplasty. However, in variance with the observation of Gu et al. [9], all long segment stenosis may not be effectively dilated. Early follow-up results reported by other workers and our own long-term evaluation suggests that relief obtained is sustained on follow-up. In fact,

M. Khalilullah and S. Tyagi: Percutaneous transluminal angioplasty

151

Fig. 4a, b. Digital subtraction angiogram of the abdominal aorta and iliac arteries showing a severe long-segment stenosis of left common iliac artery before angioplasty, and b restoration of normal vessel lumen after angioplasty a

b

Table 2. Balloon angioplasty of aorta in Takayasu arteritis ~

Authors

Patients (n)

Ballon diameter (mm)

Result Comment

Aorta at stenosis Diameter/% Stenosis Before

Khalilullah et al. (1987) [14] Gu et al. (1988) [9] Park et al. (1989) [10] Kumar et al. (1989) [11] Sharma et al. (1990) [12] Current series ~

4

12-20

9

10

3

10-12

4

8-15

2

-

35

7-20

Follow-up Complications

Duration (months)

Comment

No

5-14

Continued improvement

Aorta dissection : 1

3-28

After

All dilated

7.3mm

13.9mm

Long stenosis All dilated

4.1mm

8.7mm

All dilated

75%

37%

No

12-38

All 4 dilated

-

No

2-33

All dilated

85%

residual stenosis 6 months Hypertension improved in 19 (86.4%) Hypertension improved

Restenosis in 2 renal arteries after 4-7 months: redilated Hypotension = 1 No recurrence Blood urea increased = 1 Hypertension = 11 Renal artery dissection (including 2 aortic with occlusion = 1 stenosis) , Cure = 3, relieved = 6 No Restenosis in 1: redilated Nine patients hypertension: cure = 4, improved = 3, failed = 2 Renal artery dissection Renal-restenosis 5/ =1 36(13.9%): redilated Pseudoaneurysm at Hypertension: cure = puncture site = 1 43,6%, improved = 41% Subclavian artery Subclavian- restenosis: 1 = thrombosis = 1 redilated

a Papers reporting single cases are not included

This may be because of dense transmural fibrosis which underlies stenosis in Takayasu arteritis making the lesions resistant to dilatation. Review of published results also indicate that balloon angioplasty is a highly successful method for correcting renal artery stenosis due to Takayasu arteritis (Table 3). Restenosis rate is low compared to that reported for atherosclerotic disease. This may be because angioplasty is performed in chronic inactive stage when the disease has little tendency for progression. Absence of atherosclerotic progression, which also contributes to restenosis, may be another factor contributing to lower restenosis rate. Our experience and review of published results (Table 3) suggest that successful renal angioplasty leads to improvement in hypertension in about 85% of patients. The improvement is sustained on follow-up.

Subclavian angioplasty There is reluctance to use balloon angioplasty for stenosis of the brachiocephalic arterities because of the possible complications of cerebral embolism. However, our experience and review of cases previously published [5, 10, 11] suggests that subclavian artery stenosis due to Takayasu arteritis can be dilated with high success and low complication rate (Table 3).

The inflammatory, nonulcerative nature of the lesions may decrease the potential of embolic complications c o m p a r e d with atherosclerotic stenosis. Similar to stenotic lesions of renal arteries, subclavian artery stenosis may also be resistant to dilatation and require inflation of the balloon at high pressure (2-16, mean 7.9 _+ 3.4atm) for adequate dilatation. Follow-up of successfully treated patients show sustained relief of stenosis. Angloplasty of c o m m o n iliac artery stenosis is highly effective and on follow-up, produces sustained relief from claudication.

Conclusion Our own and published results allow the conclusion that stenotic lesions due to Takayasu arteritis can be effectively dilated. The procedure is safe and produces sustained i m p r o v e m e n t on follow-up. Therefore, P T A should be considered the treatment of choice particularly for discrete stenotic lesions due to Takayasu arteritis. Surgery should be performed in cases of failure of P T A or for total occlusions.

Acknowledgment. We thank

Dr. R. Arora, Dr. U.A. Kaul, Dr. K.K. Sethi, Dr. D.S. Gambhir, Dr. M. Nair for their invaluable assistance.

M. Khalilullah and S. Tyagi: Percutaneous transluminal angioplasty

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