A Novel Approach to the Balloon Angioplasty of a Native Discrete Severe Coarctation of the Aorta in the Management of Hypertension

Coarctation of the aorta (CoA) is one of the most frequently occurring congenital heart defects.1–3 Transcatheter therapy for the treatment of coarctation is efficacious, with acceptable morbidity and mortality rates.1,4,5 The contemporary approach is primary stent implantation; however, the results of balloon angioplasty in children and young adults are comparable to the outcomes following primary stent placement.1,4,6,7 A routine follow-up is recommended for patients with repaired CoA in order to have a thorough inspection and timely treatment when necessary.8 We describe a successful intervention and its late follow-up results in an adult with severe discrete CoA and severe refractory hypertension treated with balloon angioplasty using a novel bidirectional approach. A 31-year-old man with diagnosis of severe CoA (near interruption) and severe refractory hypertension was referred to the intervention clinic 4 years ago. Physical examination revealed an amplified second heart sound. Radial pulses were normal but the femoral pulses were delayed and weak. The medications were high dose β-blocker, angiotensin-converting enzyme (ACE) inhibitor, calcium channel blocker, and diuretics. Despite this medication the blood pressure (BP) of the patient remained >210/100 mm Hg at that time in the upper extremities. The BP of the lower extremities of the patient was 100/70 mm Hg at that time. Chest roentgenogram showed a cardiothoracic ratio of 46% with no marker of congestive heart failure. Echocardiography expressed CoA with the gradient of 105 mm Hg with an ejection fraction of 55% and mild left ventricular hypertrophy (LVH). Patent ductus arteriosus and bicuspid aortic valve were not seen. Electrocardiography also showed mild LVH with no signs of ischemia. Cardiac catheterization was performed showing normal coronary arteries. Angiography revealed that the CoA was due to severe discrete (near interruption) aortic narrowing after the left subclavian artery (length <10 mm; diameter <1 mm) (Figure 1). The general fundamentals of the technique used for balloon angioplasty have been reported previously9,10 but we couldn’t negotiate retrogradely the straight tip stiff guide wire (GW) through the lesion, therefore we selected the antegrade approach through the left brachial artery. Twenty-five thousand international units of heparin was given intravenously as soon as the arterial introducer was placed. When we began doing this procedure we incorporated several recommendations for reducing the risk of early complications. First by intraarterial infusion of a combination of verapamil and nitroglycerin we gradually declined the proximal BP to 135 mm Hg; this may reduce the dissecting complication of the procedure. When the 0.014-in GW has passed the lesion antegradely, the first inflation with one 4×20 mm coronary balloon took place, then retrograde passing of the 0.035-in GW was done through the right femoral approach and another inflation with sequential increase in balloon size was performed until the indentation caused by the coarctation was eliminated. Hemodynamic measurements and aortic angiography were performed immediately before and after each inflation of the coarctation site. The procedure we followed was to insert the next larger balloon size—without exceeding the diameter of the aorta at the level of the diaphragm—and to repeat the procedure if the residual peak systolic pressure gradient still exceeded 20 mm Hg. Angiogram before balloon angioplasty. Acute Response. Measurement of the gradient across the site of coarctation and aortography immediately after the final 15 mm balloon inflation led to reduction in gradient to zero. Postdilatation aortography showed that the diameter of the stenotic region was increased and widely reconstructed (Figure 2). Neither paradoxical hypertension nor postcoarctectomy syndrome was observed after dilation of coarctation. The procedure was successful and the patient was discharged the following day. Acute response after balloon angioplasty. Midterm Results. A follow-up computed tomography (CT) scan angiography prescribed after 4 months was normal. Echocardiography and electrocardiography findings after the procedure were normal. Up to 6 months after the procedure the patient’s hypertension was controlled only by atenolol 25 mg/d and then gradually increased and additive amlodipine 5 mg/d was prescribed. Late Response. No adverse effects have occurred in 4 years and the patient has presented regularly with controlled BP and consistent use of double antihypertensive drugs. Echocardiography comparisons showed an obvious reduction in LVH. No cerebrovascular accident was detected in the 4 years after procedure. Angiography after 4 years was within normal findings (Figure 3). Control angiogram after 4 years. Early screening of hypertension is essential for early intervention and decreasing cardiovascular morbidity and mortality in adulthood.9 A substantial number of adults with CoA haven’t been diagnosed due to lack of symptoms, while symptoms might be exposed during the examination for systemic hypertension.11 Several reports have been published regarding the comparison of invasive treatment methods of CoA (endovascular and surgical). The immediate improvement in hypertension and morbidity are similar across all groups. However, there is not consistency in authors’ findings regarding the late outcomes.12,13 Reports of long-term outcomes after balloon angioplasty of CoA in adolescents and adults indicated low reintervention probability in adult patients.4,14 Also, aortic dissection and aneurysm formation were not encountered.14 In our case, in spite of a complex procedure of balloon angioplasty, early response of pressure gradient was dramatic and the long-term follow-up result was optimal. Bidirectionally, a femoral and brachial artery approach that was successfully applied to a patient with complete and tight aortic obstruction shows that balloon angioplasty could be an alternative therapy for this kind of patient. In a well-equipped catheterization lab, gradual inflation with sequential increase in balloon size from both sides of the CoA might be a practical and acceptable treatment, while more studies with a greater number of patients are needed. The role of invasive treatment of CoA in the management of hypertension is a controversial issues in previous studies.15–17 As an important point in this case, we faced a gradual increase in blood pressure after 6 months of angioplasty despite a 4-year course of acceptable angiography. Musto and colleagues18 reported that endovascular treatment of native or recurrent CoA in adolescent and adult patients is safe but with persistent hypertension in one-third of cases; thus, they recommend careful clinical follow-up in these patients. Ozkokeli and colleagues19 reported that in the adult patients who underwent surgery for aortic coarctation, diastolic and systolic blood pressure decreased significantly, but in the older age group hypertension gradually increased despite surgery. To minimize the risk of persistent hypertension, elective repair of coarctation should be performed within the first year of life.20