Abdominal and thoracic aortic aneurysm repair: procedures forecast

Below is an excerpt from, “Global Dynamics of Surgical and Interventional Cardiovascular Procedures, 2015-2022,” (Report #C500 described, available online).

Selection of specific management protocols for patients with aortic aneurysms depends on the disease morphology as well as patient’s age, overall health status, and comorbidities involved. In cases involving smaller and relatively stable abdominal or thoracic aortic aneurysm (AAA or TAA), watchful waiting represents a commonly preferred approach. Radical surgical or endovascular interventions are generally reserved for cases when the diameter of the aneurismal sac is larger than 5cm to 5.5cm, or the annual expansion rate exceeds 1.0 cm, or when the aneurysm becomes symptomatic.

Surgical Repair of Aortic Aneurysms

Prior to the advent of AAA/TAA endovascular repair tools and techniques, a highly invasive and risky surgical repair procedure constituted the only curative option for patients with advanced and rupture prone aortic aneurysm. Conducted under the general anesthesia the procedure takes a few hours and entails a major and highly traumatic operation with a 10-15 inch cut in abdominal wall, clamping and isolation of aneurysmic segment of aorta, incision into the aneurysm, evacuation of the clot contained within, placement of a synthetic graft, and wrapping of the graft with remnants of the aortic wall.

The typical surgical aneurysm repair is associated with a substantial (5% to 8%) mortality rate and serious complications, such as stroke, myocardial infarction, renal failure etc.

Due to the close proximity to the heart, the risk and complication rates of surgical intervention for aneurysm repair on the thoracic aorta increase multifold resulting in an average procedural mortality rate of up to 30 percent.

The high cost of the procedure is largely the result of extended ICU and hospital stays, which can last upwards of a week (but average roughly 10-12 days). Further, postoperative recovery may require up to six additional weeks subsequent to discharge, making temporary disability a major consideration for many patients.

Notwithstanding these drawbacks, open surgical aortic aneurysm repair is still commonly regarded as highly effective treatment modality that virtually eliminates the risk of aneurismal sac rupture and does not require extensive postoperative follow-up exams or revisions.

However, because of high prevalence of elderly and health-impaired persons in diagnosed aortic aneurysm caseloads and traumatic nature of AAA/TAA surgery, only a fraction of the patients who could benefit from surgical aneurysm repair is deemed eligible for such a procedure.

Abdominal Aortic Aneurysm Repair with Endovascular Stent-Grafts

During the past two decades, advances in interventional technologies paved the way for the advent of a considerably less invasive and risky endovascular AAA repair procedure. The procedure involves a transcatheter deployment of the specially designed endovascular prosthesis (typically combining sealing functions of the vascular graft and full or partial stenting support structure) into a defective segment of aorta with the goal of excluding the aneurysmal sac from blood circulation.

The endovascular stent-grafts (SGs) – which come both in self-expanding or balloon-expandable versions – are typically anchored to an undamaged part of the aorta both above and below the aneurysm via a compression fit or/and with a special fixation mechanism like hooks, barbs, etc.

To accommodate a great morphological diversity of aortic aneurysms the vast majority of endovascular SGs is employing a modular design concept providing the aorto iliac, bifurcated and straight tubular device configurations to cover a variety of AAA indications. Several SG systems also feature an open stenting structure at proximal end to enable suprarenal device deployment required in about 30% to 35% of all AAA cases warranting intervention.

In its idea, the endovascular repair of abdominal aortic aneurysm was intended to produce clinical outcomes comparable to these yielded by the open surgery, while reducing the associated trauma, recovery time, morbidity and the overall treatment cost. It was also generally expected that availability of less-invasive endovascular treatment option would allow to extend caseloads coverage to sizable rupture-prone AAA patient subsets who are poor surgical candidates.

Limitations of Endovascular AAA Repair

Findings from numerous clinical studies and real-life experience in the field seem to indicate that endovascular aortic aneurysm repair via stent-graft placement tends to provide immediate procedural outcomes comparable to these obtainable with open surgery. Furthermore, the typical ICU and hospital stay for endovascular AAA repair averages 2 days (though it may last twice longer for patients with significant comorbidities). All of these translates into reduced inpatient costs of AAA repair relative to open surgery, although the high price of stent-grafting devices largely offsets these cost savings. Post-discharge recovery is also shortened from weeks or months to an average 7-10-day period.

Unfortunately, comparative long-term clinical efficacy and cost-effectiveness of the endovascular approach to aortic aneurysm repair appears to be problematic due to unavoidable shortcomings of available aortic stent-graft designs and complications associated with their less than perfect performance in situ.

The major problems associated with the endovascular AAA repair approach include relatively high incidence of endoleaks (up to 15%), endotension, and device failure, which multiply the risk of catastrophic aneurysm rupture and necessitate costly revisions (in up to 35% of the cases) as well as long-term (or life-long) patient surveillance (with mandatory imaging exams). Due to that, the actual overall cost of endovascular repair in many considerably exceeds expenses incurred in traditional open surgery.

Another limitation of endovascular stent-grafting relates to its ability to accommodate complex aortic aneurysm morphology and branch involvement. Based on some end-user and industry reporting, only about 50% of patients that develop intervention-warranting AAAs are considered good candidates for endovascular repair with currently available product configurations.

According to some recent reporting, endovascular aneurysm repair (EVAR) treatment with certain stent grafts also appears to be associated with higher late mortality rates (due to aneurysm rupture) compared to surgical AAA repair. Based on available long-term follow-up data, mortality in AAA patients retrofitted with the market-leading SG averages 1.3% and 1.5% at four and five years compared to 0.7% and 0.9% for AAA surgery.

Endovascular Repair of TAA

Introduced in Europe and the U.S. in 1998 and 2005, accordingly, endovascular techniques for aneurysm (and aortic dissection) repair on thoracic aorta represented a logical extension of the very same basic concept and technology platforms that enabled the development of AAA stent-grafts.

Because of extremely high mortality and morbidity rates associated with TAA surgery, the need for minimally invasive endovascular treatment option was even more compelling than that in AAA case.

Similar to AAA endovascular repair devices, TAA stent-grafts are intended to minimize the risk of catastrophic thoracic aortic aneurysm rupture via effective exclusion (isolation) of the aneurismal sac from blood circulation.

Unlike AAA implants, commercially available TAA stent-grafting devices feature relatively simple tubular unibody architecture with sealing cuffs (or flanges) at proximal and distal end.

Insertion of TAA SGs is done under fluoroscopic guidance via a singular femoral puncture with the use of standard transcatheter techniques. Depending on the aneurysm morphology, one or two overlapping devices might be used to ensure proper aneurismal sac isolation.

The average ICU and hospital stays and post-discharge recovery period for endovascular TAA repair procedure are generally similar to these for AAA stent-grafting intervention.

Although practical clinical experience with endovascular repair of thoracic aortic aneurysm remains somewhat limited, findings from European and U.S. clinical studies with TAA stent-grafting tend to be very encouraging. Based on these findings, stent-grafting of rupture-prone aneurysm on ascending thoracic aorta can be performed with close to perfect technical success rate yielding radical reduction in intraoperative mortality and complications compared to TAA surgery as well as impressive improvement in long-term patient survival.

Similar to AAA endografting, the main problems associated with the use of TAA SG systems include significant incidence of endoleaks and occasional device migration which require reintervention.

Aortic Aneurysm Repair Procedure Volumes

Based on the industry reporting, national and international healthcare authority data, and MedMarket Diligence estimates, in 2015, approximately 915 thousand patients worldwide were diagnosed with rupture-prone abdominal or thoracic aortic aneurysms and aortic dissections warranting radical intervention, of which roughly 359.5 thousand (or about 39.3%) were actually referred for surgical or transcatheter treatment. Covered APAC market geography (with combined population of about 2,63 billion) accounted for the largest 37.6% share of all aortic aneurysm repairs performed, followed by the U.S. with 25.6%, largest Western European states with 21.3% and the rest-of-the-world with the remaining 15.5%.

Endovascular stent-grafting techniques were utilized in approximately 162.5 thousand aortic aneurysm repair procedures in 2015, which included an estimated 133 thousand AAA-related and about 29.5 thousand TAA-related interventions (including these targeting selected thoracic aortic dissections).

The cited figures reflected a disparity both in the relative volumes of treated AAA and TAA patients and, especially, in the share of these managed with the less invasive EVAR techniques. The latter indicator was the highest for the U.S. (~75%), compared to 52% for Western Europe, 39% for APAC and only 36.6% for the ROW market geography.

During the forecast period covered in the report, the total global volume of endovascular aortic aneurysm repairs is projected to grow 5.7% per annum to approximately 243 thousand procedures, combining a 5.5% annual expansion in AAA-related interventions with a 6.6% average annual increase in TAA (aortic dissection)-related interventions.

Projected healthy gains in endovascular aortic aneurysm repair procedures should reflect continuous penetration of non-surgical (no option) AAA and TAA patient caseloads, coupled with significant incursion into surgery-eligible patient subsets both in AAA, TAA, and aortic dissection indications. Increasing reliance on utilization of less traumatic AAA and TAA stent-grafting techniques will be expedited by ongoing qualitative improvements in the endograft and delivery tools design that keep yielding more reliable, durable, versatile, and end-user friendly systems with reduced propensity to mechanical and functional failure (device kinking, fracture, endoleaks, migration, etc.) and associated clinical complications.

The largest relative gains in AAA and TAA EVAR procedures (10.9% and 11.8%, accordingly) can be expected in covered APAC territories (mostly China and India) and grossly underserved ROW zone (6.5% and 7.5%). Largely mature U.S., Western European (and Japanese) markets are likely to register a low single digit advances in utilization of endovascular AAA/TAA repair techniques.

The global procedure volume forecast for aortic aneurysm repair is presented below.

Projected Dynamics of Aortic Aneurysm Repair Procedures,
World Total, 2015-2022 (#000)

Indications / Procedures20152016201720182019202020212022CAGR 2016-2022
Total EVAR AAA/TAA Procedures1516.317.618.920.221.522.824.16.70%
Diagnosed AAA & TAA Caseloads1651701751801851901952002.80%
Treated AAA & TAA Patients5658.56163.56668.57173.53.90%
Abdominal Aortic Aneurysm (AAA) Repair
Treated AAA Patient Caseloads45474951535557593.90%
Surgical Repair Procedures33343536373839402.80%
Endovascular Repair Procedures12131415161718196.50%
Thoracic Aortic Aneurysm (TAA) Repair
Treated TAA Patient Caseloads1111.51212.51313.51414.53.90%
Surgical Repair Procedures88.28.48.68.899.29.42.30%
Endovascular Repair Procedures33.33.63.94.24.54.85.17.50%
Total Surgical AAA/TAA Repairs4142.243.444.645.84748.249.42.70%

Notes: AAA = abdominal; aortic aneurysm. EVAR = endovascular aneurysm repair. TAA = thoracic aortic aneurysm.

Source: MedMarket Diligence, LLC; Report #C500. (Full cardiovascular procedures report online.)

Source: MedMarket Diligence, LLC; Report #C500. (Full cardiovascular procedures report online.)

 

Interventional and Surgical Cardiovascular Procedure Volumes

Cardiovascular diseases (CVDs) are a variety of acute and chronic medical conditions associated with an inability of the cardiovascular system to sustain an adequate blood flow and supply of oxygen and nutrients to organs and tissues of the body. The CVD conditions may be manifested by the obstruction or deformation of arterial and venous pathways, distortion in the electrical conducting and pacing activity of the heart, and impaired pumping function of the heart muscle, or some combination of circulatory, cardiac rhythm, and myocardial disorders.

These diseases are treated via the following surgical and interventional procedures:

  • Coronary artery bypass graft (CABG) surgery;
  • Coronary angioplasty and stenting;
  • Lower extremity arterial bypass surgery;
  • Percutaneous transluminal angioplasty (PTA) with and without bare metal and drug-eluting stenting;
  • Peripheral drug-coated balloon angioplasty;
  • Peripheral atherectomy;
  • Surgical and endovascular aortic aneurysm repair;
  • Vena cava filter placement
  • Endovenous ablation;
  • Mechanical venous thrombectomy;
  • Venous angioplasty and stenting;
  • Carotid endarterectomy;
  • Carotid artery stenting;
  • Cerebral thrombectomy;
  • Cerebral aneurysm and AVM surgical clipping;
  • Cerebral aneurysm and AVM coiling & flow diversion;
  • Left Atrial Appendage closure;
  • Heart valve repair and replacement surgery;
  • Transcatheter valve repair and replacement;
  • Congenital heart defect repair;
  • Percutaneous and surgical placement of temporary and permanent mechanical cardiac support devices;
  • Pacemaker implantation;
  • Implantable cardioverter defibrillator placement;
  • Cardiac resynchronization therapy device placement;
  • Standard SVT & VT ablation; and
  • Transcatheter AFib ablation

In 2016, the cumulative worldwide volume of these procedures is projected to approach 15.05 million surgical and transcatheter interventions. This will include:

  • roughly 4.73 million coronary revascularization procedures via CABG and PCI (or about 31.4% of the total),
  • close to 4 million percutaneous and surgical peripheral artery revascularization procedures (or 26.5% of the total);
  • about 2.12 million cardiac rhythm management procedures via implantable pulse generator placement and arrhythmia ablation (or 14.1% of the total);
  • over 1.65 million CVI, DVT, and PE targeting venous interventions (representing 11.0% of the total);
  • more than 992 thousand surgical and transcatheter heart defect repairs and valvular interventions (or 6.6% of the total);
  • close to 931 thousand acute stroke prophylaxis and treatment procedures (contributing 6.2% of the total);
  • over 374 thousand abdominal and thoracic aortic aneurysm endovascular and surgical repairs (or 2.5% of the total); and
  • almost 254 thousand placements of temporary and permanent mechanical cardiac support devices in bridge to recovery, bridge to transplant, and destination therapy indications (accounting for about 1.7% of total procedure volume).

Below is illustrated the overall global growth for each of the major categories of procedures through 2022.

Source: MedMarket Diligence, LLC; Report #C500.  (Full report available online.)

There is considerable variation in the growth of cardiovascular procedures globally, but most growth is coming out of Asia/Pacific. For example, within the area of venous interventions, the growth in the use of endovenous ablation for chronic venous insufficiency is markedly higher in Asia/Pacific than in other regions, though the U.S. will remain the largest volume of these procedures.

Source: MedMarket Diligence, LLC; Report #C500.  (Full report available online.)


“Global Dynamics of Surgical and Interventional Cardiovascular Procedures, 2015-2022” (Report #C500), published August 2016. See description, table of contents, list of exhibits at link. Available for purchase and download from link.

Peripheral Stenting Procedures and Markets

First introduced about two decades ago as a bailout technique for suboptimal or failed iliac angioplasty, peripheral vascular stenting gradually emerged as a valuable and versatile tool for a variety of primary and adjuvant applications outside the domain of coronary and cerebral vasculature.  Today, peripheral vascular stenting techniques are commonly employed in the management of the most prevalent occlusive circulatory disorders and other pathologies affecting the abdominal and thoracic aortic tree and lower extremity arterial bed. Stents are also increasingly used in the management of the debilitating conditions like venous outflow obstruction associated with deep venous thrombosis and chronic venous insufficiency.

Notwithstanding a relative maturity of the core technology platforms and somewhat problematic opportunities for conversion to value-adding peripheral drug-eluting systems, peripheral vascular stenting appears to have a significant room for qualitative and quantitative growth both in established and emerging peripheral indications.

Source: MedMarket Diligence, LLC; “Global Market Opportunities in Peripheral Arterial and Venous Stents, Forecast to 2020.” Report #V201. Order online.

 

Peripheral Stenting Worldwide: Arterial, Venous, BMS, DES, AAA, TAA

First introduced about two decades ago as a bailout technique for suboptimal or failed iliac angioplasty, peripheral vascular stenting gradually emerged as a valuable and versatile tool for a variety of primary and adjuvant applications outside the domain of coronary and cerebral vasculature.  Today, peripheral vascular stenting techniques are commonly employed in the management of the most prevalent occlusive circulatory disorders and other pathologies affecting the abdominal and thoracic aortic tree and lower extremity arterial bed. Stents are also increasingly used in the management of the debilitating conditions like venous outflow obstruction associated with deep venous thrombosis and chronic venous insufficiency.

Notwithstanding a relative maturity of the core technology platforms and somewhat problematic opportunities for conversion to value-adding peripheral drug-eluting systems, peripheral vascular stenting appears to have a significant room for qualitative and quantitative growth both in established and emerging peripheral indications.

A panoply of stenting systems are available for the management of occlusive disorders and other pathologies affecting peripheral arterial and venous vasculature. Systems include lower extremity bare metal and drug-eluting stents for treatment of symptomatic PAD and critical limb ischemia resulting from iliac, femoropopliteal and infrapopliteal occlusive disease; stent-grafting devices used in endovascular repair of abdominal and thoracic aortic aneurysms; as well as a subset of indication-specific and multipurpose peripheral stents used in recanalization of iliofemoral and iliocaval occlusions resulting in CVI.

In 2015, these peripheral stenting systems were employed in approximately 1.565 million revascularization procedures worldwide, of which the lower extremity arterial stenting accounted for almost 1.252 million interventions (or 80.9%), followed by AAA and TAA endovascular repairs with 162.4 thousand interventions (or 10.5%) and peripheral venous stenting used in an estimated 132.6 thousand patients (or 8.6% of the total).

The U.S. clinical practices performed almost 528 thousand covered peripheral arterial and venous procedures (or 34.1% of the worldwide total), followed by the largest Western European states with over 511 thousand interventions (or 33.1%), major Asian-Pacific states with close to 377 thousand interventions (or 24.4%), and the rest-of-the-world with about 131 thousand peripheral stent-based interventions (or 8.4%).

Below is illustrated the global market for peripheral stenting by region in 2016 and by segment from 2014 to 2020.

Source: MedMarket Diligence, LLC; Report #V201. Available online.

 

Source: MedMarket Diligence, LLC; Report #V201. Available online.