Surgical Management in Chronic Thromboembolic Pulmonary Hypertension. Michael Bates, MD, FACS Ochsner Health System, New Orleans, LA

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1 Surgical Management in Chronic Thromboembolic Pulmonary Hypertension Michael Bates, MD, FACS Ochsner Health System, New Orleans, LA

2 Disclosures No industry conflicts I am a surgeon and always disclose my bias

3 Terms of engagement EMBOLECTOMY = Acute Pulmonary Embolism ENDARTERECTOMY = CTEPH

4 Incidence Acute PE and CTEPH are underdiagnosed and more common than generally appreciated It is estimated that 0.5% of Acute PE patients develop CTEPH However, most CTEPH patients have no antecedent history of PE Current estimates are that 100,000 people have PH that could be treated surgically

5 Pathogenesis Embolic material may overwhelm the lytic system Total occlusion may prevent lysis from occurring Lytic system may be abnormal Catheters, leads, filters and tumors may be an ongoing source

6 What happens to the clot? 1. Organized clot becomes canalized and produces endothelialized channels with fibrous septa (channels or webs) 2. Complete fibrous organization of the fibrin clot does not canalize leading to a solid mass of dense fibrous connective tissue completely obstructing the arterial lumen

7 Why does PH occur? Many factors are involved Seen even when less than 50% of the vascular bed is occluded by thrombus Redirected pulmonary blood flow may create a vasculopathy in the small precapillary blood vessels Sympathetic neural connections cross talk between lungs Hormonal changes

8 Clinical Presentation 50% chest pain/tightness Hemoptysis Cor pulmonale Hypoxia/cyanosis (late), PO2 ranges from 50 to 83 torr PFT usually normal, except DLCO is often reduced

9 Diagnosis Standardized workup Chest radiograph: regions of oligemia, enlarged central arteries and RV ECG: RV hypertrophy (right axis deviation, R-wave in V1), RA hypertrophy PFT: mostly normal except for decreased DLCO VQ scan: when normal rules out CTEPH Pulmonary Angiogram: still the gold standard CT, LHC and echo scan can add to the workup

10 ECG Patient 1: RA enlarged, RVH, R Axis Patient 2: R Axis, RVH, R Bundle

11 CXR

12 CXR

13 Pulmonary Angiography Should be performed whenever CTEPH is the suspected cause of PH Organized appear as unusual filling defects, webs, bands, or complete occlusions Recanalized vessels appear to have scalloped or serrated luminal edge Vessel wall thickening and vessel dilation may make the lumen appear normal Distal vessels demonstrate rapid tapering and prunning

14 Right Pulmonary Angiogram

15 CT scan

16 Medical Therapy Consists of Anticoagulation Prevent future emboli Limit thrombus formation in low flow areas Inferior vena cava filters Lytic agents are incapable of altering the chronic clot RV failure treated with diuretics and vasodilators, but effects are transient Prognosis is unaffected by medical therapy which is mainly supportive

17 Natural History Dismal without surgery Progressive RV failure Diagnosis usually made late when patients have severe PH (>40 mmhg) and symptoms of right heart failure Severity of PH at diagnosis inversely correlates with survival Riedel: mean survival 28 months form diagnosis (Chest 1982)

18 Types Type 1: 15% Central thrombotic material must be removed prior to endarterectomy Type 2: 55% No major vessel thrombus, thickened intima, webs, endarterectomy plane raised in main, lobar and segmental arteries Type 3: 30% distal disease in segmental and subsegmental arteries. Most Difficult and usually indwelling catheters or wires Type 4: not CTEPH, primary PH due to small vessel disease with secondary thrombus due to stasis

19 Type 1

20 Type 2 No major vessel thrombus, thickened intima, webs, endarterectomy plane raised in main, lobar and segmental arteries

21 Type 3 distal disease in segmental and subsegmental arteries. Most Difficult and usually indwelling catheters or wires

22 Type 4 not CTEPH, primary PH due to small vessel disease with secondary thrombus due to stasis

23 Surgery vs Transplant Waitlist mortality, higher risk of surgery and lower survival (85% one year, 50% five year) with Transplant 95% 5 year survival with endarterectomy Endarterectomy is considered permanently curative Risk of rejection and rejection

24 Endarterectomy PEA offers excellent symptomatic and prognostic benefits the 5-year mortality rate is 90% in patients who remain untreated 95% 5 year survival with surgery

25 Pulmonary Thromboendarterectomy First performed 1960, Allison Thorax 1960 UCSD, Braunwald cases, majority since 1990 Mean age 54 (3-85) 1/3 concomitant cardiac surgery (PFO 26%, CABG 8%) Mortality 9% to 5% to 2% over 35 years

26 Indications Hemodynamic, alveolo-respiratory, and prophylactic (Moser Circulation 1965) Prevent RV failure, prevent proximal propagation and prevent secondary arteriopathic changes There is no degree of RV dysfunction, PVR or PA pressure that excludes patients from surgery Most are Class III and IV NYHA

27 Principles of the Operation Bilateral Endarterectomy Median sternotomy CPB and circulatory arrest (20 min at 20 C) Excellent visibility and bloodless field Define true endarterectomy plane of the media Complete and distal endarterectomy

28 Operation Eversion technique Start proximal Work distal into segmental and subsegmental arteries Bloodless field with circ arrest No bronchial flow

29 Instruments for Endarterectomy Double action forceps to maintain control into the subsegmental arteries during eversion endarterectomy Jameison Suction Irrigators for extended endarterectomy in the correct plane over a long distance Knife for entering the initial plane of dissection

30 The correct plane Critical to success and the reason for circulatory arrest Ideal layer pearl white plane develops easily No residual yellow plaque Too deep there is reddish color of the adventitia Eversion technique must be employed

31 Right Pulmonary Artery Main PA opened down to lower lobe branch Developing the plane in the adventitia posteriorly Important to start in the correct plane and work distally

32 Eversion Technique

33 Specific Complications Persistent PH: may resolve after a few days with relaxation of small vessels and resolution of pulmonary edema Persistent PH due to Type 4 carry most of the current operative mortality and is an error in diagnosis Reperfusion injury: radiologic opacity seen in 10%. When severe manifests as pulmonary edema, ET secretions and desaturation

34 Hemodynamic Results 95% Class III-IV preop, 95% Class I-II at 1 year RV geometry rapidly normalizes TR resolves, usually immediately Tricuspid repair is not performed Long term quality of life is almost equal to normal individuals

35 CASE 1 35 yo woman 3 months s/p PE with history DVT PAP 81/33 (52), RAP 29, severe RV dysfunction, Severe TR Class IV NYHAA 6 mi walk 390 m Bilateral Pulmonary Endarterectomy with circulatory arrest

36 Left Endarterectomy

37 Right Specimen

38 Post OP Normal RV function, No TR PAP 50/17 (31) 6 min walk 670 m NYHA class I 18 months normal PAP, PH infusion stopped

39 CASE 2 Sats 75% PO2 90 on FI 100 PAP Super systemic CVP 22 Sats 100% PO2 590 on FI100 Home POD 5 on no O2 no PH Meds

40 Case 3 BMI 52 PO2 60 on FI 100 PAP Systemic CVP 26 PO2 360 PAP 45 CVP 10 Discharged POD 5 no O2 and no meds

41 THANK YOU