Cardiac rhythm disorders, also called arrhythmias or dysrhythmias, encompass a variety of relatively common acute and chronic conditions characterized by recurrent distortions in the electrical and contractile activity of the heart, which may cause clinically significant and progressive hemodynamic deficits and cardiopulmonary impairment.
According to the available statistics from the American Heart Association (AHA) and Heart Rhythm Society, symptomatic cardiac arrhythmias effect over 10 million Americans and account for approximately 20% of all chronic conditions treated by cardiologists in the United States.
The rate and rhythm of the heart are determined by the intrinsic rhythmicity of special tissues and structures within the heart wall muscle generated by the heart’s natural electrophysiological mechanism. Normal cardiac rate and rhythm ensure continued uninterrupted blood flow an associated supply of oxygen and nutrients to the brain and other vital organs. Irregularities in the rate, rhythm, or origin of a stimulus leading to myocardial contraction can potentially interrupt normal blood circulation, causing inadequate function of important body systems, stroke or sudden cardiac arrest and death. Heart pacing disorders usually degenerate and worsen over time.
Although cardiac arrhythmias may be triggered by congenital heart defects, in which the electrical system of the heart does not develop properly, non-congenital heart disorders are believed to be the most common causes of chronic arrhythmias. The latter is particularly true for ischemic heart disease, which results in reduced blood flow and oxygen delivery to heart tissue, and heart tissue scarring typically caused by myocardial infarction. Other causes of arrhythmia include abnormal blood and tissue concentrations of certain minerals; abnormalities of the autonomic nervous system, which is involved in cardiovascular regulation; stress; and use of alcohol, caffeine, illicit drugs, and tobacco, as well as diet pills and some other medications.
Cardiac arrhythmias are generally categorized according to their impact on heart rates. Bradycardia is an abnormally slow resting heart rate, whereas tachycardia is an abnormally high resting heart rate. Bradycardias are most commonly associated with SA node disease and/or various forms of heart block.
Tachycardias are usually classified by their origination site and may be subdivided into two broad categories, specifically, supraventricular tachycardias (SVTs) and ventricular tachycardias (VTs).
Below are shown the projected implantable pump generator placements by region from 2015 to 2022. These include pacemaker placements, implantable cardioverter defibrillator placements, and cardiac resynchronization therapy placements.
Stents are implantable devices designed as endoluminal scaffolds to maintain patency following recanalization of occluded or structurally compromised vascular (and non-vascular) circulatory conduits that enable energy supply and metabolic exchange in various organs and tissues of the human body. Palliative stenting has been routinely used for decades in the management of acute and chronic obstructions of gastro-intestinal, pulmonary and urinary tracts secondary to benign or malignant neoplasms or other cite-specific or systemic pathologies. However, a real explosion in utilization of stents was triggered in the early 1990s by the advent of vascular stenting devices, which allowed radically improved clinical outcomes of balloon angioplasty and supported its emergence as the first choice treatment modality for occlusive peripheral and coronary artery disease (PAD and CAD). By the end of 2014, more than three quarters of patients with acute and chronic arterial occlusions warranting intervention were referred for angioplasty-based therapy, which entailed placement of stenting devices in over 80% of commonly performed peripheral revascularization procedures.
To be accepted in clinical practices, stenting implants should satisfy a number of general and application-specific requirements relating to device biocompatibility, functional performance, and end-user and patient friendliness which are summarized in the exhibit below. In very general terms, stenting device biocompatibility refers to minimization of hostile immune responses (and other local and systemic adverse reactions) that are inevitably triggered by a direct contact of any implantable medical device with living tissues and bodily fluids in situ. For understandable reasons, biocompatibility depends primarily on the implant surface material, including such characteristics as chemical inertness and stability, corrosion resistance, etc. The stenting device biocompatibility can also be effected somewhat by the duration of its presence in situ and specifics of the deployment site and occlusion causing pathology.
The stent’s functional performance (or ability to maintain adequate scaffolding support and lumen patency for a desired period of time) represents a complex function of the device design/architecture and the relative static and dynamic strength of its base material. The chosen stenting device’s architecture and structural material predetermine it radial strength, longitudinal flexibility, conformability and foreshortening, as well as relative lesion coverage, fatigue and kinking resistance, circulatory flow obstruction, etc.
Finally, the stent’s end-user and patient friendliness are predicated both by the design concept of the delivery system and stenting device and refers to procedural convenience, predictability, safety, morbidity, availability of bail-out options, etc. The commonly acknowledged stenting system characteristics relating to the end-user/patient friendliness include low profile, flexibility, traceability, high radiopacity, compatibility with established transcatheter tools and techniques, ease of use and short learning curve, simplicity of retrieval in case of procedural failure, possibility of emergent /elective conversion to surgery, etc.
Selected Biomedical, Clinical and Technical Requirements for Stenting Implants
Coronary revascularization, whether by bypass graft or percutaneous coronary intervention, drives an enormous amount of medtech business. Angioplasty catheters, guidewires, and the plethora of devices in cardiothoracic surgery represent many millions in sales annually. Manufacturers pursuing growth in these areas will see big, but slowing growth rates in the U.S., while markets in Asia/Pacific reflect the growing demand for cardio technologies. Already, these markets are surpassing western markets:
While coronary applications have a long history, venous interventions have less, and procedure data shows that patient populations have not been fully tapped in any geographic region. Already, Asia/Pacific markets would appear to be on course to eclipse western markets, but not until after 2022, and will eclipse Western Europe markets before challenging the U.S.
In 2016, the cumulative worldwide volume of the cardiovascular device 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).
With few exceptions, cardiovascular technologies no longer command big premiums (like many other medtech sectors) and mature Western markets for cardio devices have already captured most of the readily available patient caseloads. The lines between different markets (device, drugs, materials) are blurring, while surgical specialists seek to slow the caseload migration to interventionalists. The epicenter of growth in utilization of advanced cardiovascular technologies and techniques is gradually shifting to emerging Asia-Pacific markets away from the increasingly stagnant U.S. and Western European marketplace. The latter reflects the sheer size of underserved patient caseloads, availability of funding, and increasing reliance on economical domestically reproduced sophisticated endovascular devices.
“In order to be successful, manufacturers, investors, healthcare providers, advisors, and others in cardiac surgery and endovascular fields need to understand the real dynamics and asymmetrical development pattern of different cardiovascular device markets in different geographies,” says Patrick Driscoll of MedMarket Diligence. “At the root of understanding the market is accurately and realistically gauging the current and future demand for, and likely usage of, specific medical and surgical technologies and procedures.”
MedMarket Diligence has published a comprehensive resource available to manufacturers, investors, and others with interest in cardiovascular technologies. “Global Dynamics of Surgical and Interventional Cardiovascular Procedures, 2015-2022,” is a worldwide competitive analysis and forecast of existing and emerging cardiovascular technologies and procedures coupled with identification and assessment of the most promising and sizable device markets.
The report covers surgical and interventional therapeutic procedures commonly used in the management of acute and chronic conditions affecting the myocardium and vascular system. The latter include ischemic heart disease (and its life threatening manifestations like AMI, cardiogenic shock, etc.); heart failure; structural heart disorders (valvular abnormalities and congenital heart defects); peripheral artery disease (and limb and life threatening critical limb ischemia); aortic disorders (AAA, TAA and aortic dissections); acute and chronic venous conditions (such as deep venous thrombosis, pulmonary embolism and chronic venous insufficiency); neurovascular pathologies associated with high risk of hemorrhagic and ischemic stroke (such as cerebral aneurysms and AVMs, and high-grade carotid/intracranial stenosis); and cardiac rhythm disorders (requiring correction with implantable pulse generators/IPG or arrhythmia ablation).
The report offers epidemiology and mortality data for the major cardiovascular conditions along with current assessment and projected procedural dynamics (2015 to 2022) for primary market geographies (e.g., United States, Largest Western European Countries, and Major Asian States) as well as the rest of the world.
Methodology. The MedMarket Diligence procedural assessments and forecasts are based on the systematic analysis of a multiplicity of sources including (but not limited to):
Latest and historic company SEC filings, corporate presentations, and interviews with product management and marketing staffers;
Data released by authoritative international institutions (such as OECD and WHO), and national healthcare authorities;
Statistical updates and clinical practice guidelines from professional medical associations (like AHA, ACC, European Society of Cardiology, Chinese, Indian, and Japanese Societies of Cardiology, etc.);
Specialty presentations at major professional conferences (e.g., TCT, AHA Scientific Sessions, EuroPCR, etc.);
Publications in major medical journals (JAMA, NEJM, British Medical Journal, Lancet, etc.) and specialty magazines (CathLab Digest, Endovascular Today, EPLab Digest, etc.);
Findings from relevant clinical trials;
Feedback from leading clinicians (end-users) in the field on device/procedure utilization trends and preferences; and
Policy papers by major medical insurance carriers on uses of particular surgical and interventional tools and techniques, their medical necessity and reimbursement.
Surgical and Interventional Procedures Covered:
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;
Surgical and endovascular aortic aneurysm repair;
Vena cava filter placement;
Mechanical venous thrombectomy;
Venous angioplasty and stenting;
Carotid artery stenting;
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;
The global market for cardiovascular devices is in the billions. Its size and association with life-saving clinical utility ensures that investors will support a surprisingly strong range of innovations in an otherwise very well-established medtech market. There is stable growth in many cardio technologies that have attained “gold standard”; aggressive growth in China, India, and Japan; and select new cardio technologies expected to rapidly seize caseload.
Report #C500, excerpted below, provides forecasts and analysis of cardiovascular surgical and interventional procedures to illustrate the volume and growth by clinical area, caseload trend, practice trend, technology introduction or regional dynamic impact.
During the forecast period 2016 to 2022, the total worldwide volume of cardiovascular surgical and interventional procedures, tracked by MedMarket Diligence, is forecast to expand on average by 3.7% per annum to over 18.73 million corresponding surgeries and transcatheter interventions in the year 2022. The largest absolute gains can be expected in peripheral arterial interventions (thanks to explosive expansion in utilization of drug-coated balloons in all market geographies), followed by coronary revascularization (supported by continued strong growth in Chinese and Indian PCI utilization) and endovascular venous interventions (driven by grossly underserved patient caseloads within the same Chinese and Indian market geography).
The latter (venous) indications are also expected to register the fastest (5.1%) relative procedural growth, followed by peripheral revascularization (with 4.0% average annual advances) and aortic aneurysm repair (projected to show a 3.6% average annual expansion).
Geographically, Asian-Pacific (APAC) market geography accounts for slightly larger share of the global CVD procedure volume than the U.S. (29.5% vs 29,3% of the total), followed by the largest Western European states (with 23.9%) and ROW geographies (with 17.3%). Because of the faster growth in all covered categories of CVD procedures, the share of APAC can be expected to increase to 33.5% of the total by the year 2022, mostly at the expense of the U.S. and Western Europe.
However, in relative per capita terms, covered APAC territories (e.g., China and India) are continuing to lag far behind developed Western states in utilization rates of therapeutic CVD interventions with roughly 1.57 procedures per million of population performed in 2015 for APAC region versus about 13.4 and 12.3 CVD interventions done per million of population in the U.S. and largest Western European countries.
The rationale for the development of drug-coated angioplasty balloons (DCBs) derives mainly from the limitations of drug-eluting stents (DES). Nonstent-based localized drug delivery using a DCB maintains the antiproliferative properties of a DES, but without the immunogenic and hemodynamic drawbacks of a permanently implanted endovascular device. Moreover, DCBs may be used in subsets of lesions where DES cannot be delivered or where DES do not perform well. Examples include torturous vessels, small vessels or long diffuse calcified lesions, which can result in stent fracture; when scaffolding obstructs major side branches; or in bifurcated lesions.
Additional potential advantages of DCBs include:
homogenous drug transfer to the entire vessel wall;
rapid release of high concentrations of drug sustained in vessel wall no longer than a week, with little impact on long-term healing;
absence of polymer, which reduces the risk of chronic inflammation and late thrombosis;
absence of a stent, preserving the artery’s original anatomy, very important in bifurcations or small vessels to diminish abnormal flow patterns; and
avoided need for lengthy antiplatelet therapy.
Currently, paclitaxel is primarily used by DCB manufacturers. Its high lipophilic property allows for passive absorption through the cell membrane and sustained effect within the treated vessel wall.
Below we illustrate the rise of drug-coated balloons for peripheral angioplasty procedures in lower extremities.
The usage of peripheral DCB in clinical practices can be expected to experience explosive growth in superficial femoral artery and femoro-popliteal below-the-knee indications to over half a million procedures annually by the year 2022. Anticipated rapid adoption of peripheral DCB technologies in the U.S. and major Asia-Pacific States (especially in China and India accounting for 95% of the covered region’s population) should work as a primary locomotive of growth of projected global procedural expansion.
Congenital heart abnormalities – which occur in an estimated 1.1% to 1.3% of infants born in the U.S. and worldwide each year – constitute leading cause of birth defect-related deaths. To-date, clinicians have identified and documented almost four dozens distinctive heart defects in newly born ranging from relatively simple and easily correctible abnormalities to complex and multiple anatomical malformations.
The most commonly encountered congenital heart abnormalities accounting for the majority of all diagnosed cases include: ventricular septal defect (VSD); tetralogy of Fallot (TOF); transposition of great vessels (TGV); atrioventricular septal defect (ASD); and coarctation of aorta (COA).
Selection of treatment protocols for congenital heart defects depends on the morphology of the abnormality and its immediate and long-term impact on cardiopulmonary function and patient’s prognosis (threat to survival).
Many asymptomatic patients with minor defects (typically representing unresolved inheritance from normal fetal development, such as trans-septal conduits that are supposed to close at birth) might be put on a “watchful waiting” regime.
Some symptomatic and functionally compromising congenital heart defects can be treated with minimally invasive percutaneous (transcatheter) techniques. To-date, percutaneous repair tools have been developed and clinically tested for several common congenital myocardial abnormalities including: patent ductus arteriosus (PDA), atrial septal defect, ventricular septal defect and patent foramen ovale (PFO). In all instances, the primary objective of the transcatheter approach was to reduce morbidity, mortality and costs associated with the procedure by achieving septal repair or closure via endovascular implantation of specially-configures occluding or sealing devices.
In cases involving complex, debilitating and life threatening congenital myocardial abnormalities (such as Tetralogy of Fallot, transposition of great vessels, etc.) one or several corrective open heart surgeries represent the only route to patient survival. Such surgeries are typically performed during the first year of infant’s life and carry a 5% risk of mortality, on average.
Source: MedMarket Diligence, LLC; Report #C500, “Global Dynamics of Cardiovascular Surgical and Interventional Procedures, 2015-2022.”
Based on the available industry data and MedMarket Diligence estimates, in 2015, approximately 387 thousand congenital heart defect repair procedures were performed worldwide, of which less invasive transcatheter interventions accounted for about 24.3% and open heart corrective surgeries for the remaining 75.7%.
For the period 2015 to 2022, the cumulative global volume of congenital heart defect repair procedures is projected to grow 1.9% per annum to approximately 444 thousand percutaneous and surgical interventions in the year 2022. The usage of transcatheter procedures can be expected to experience significantly faster 9.0% average annual growth (partially at the expense of corrective open heart surgeries for septal defects), reflecting mostly accelerated transition to minimally invasive percutaneous septal defect repair in APAC and ROW market geographies (where the latter techniques currently used only in 15% to 22% of corresponding procedures, compared to 60% to 75% in Western Europe and the U.S.).
The initial use of cerebral thrombectomy systems has been a disappointment. It is generally assumed that the situation with end-user adoption is likely to improve dramatically in two-three years from now, when results of the ongoing major U.S. and international trials with novel cerebral thrombectomy devices become available. Growth will exceed 11% annually through 2022.
#4 Below-the-knee drug-coated balloon angioplasty for superficial femoral artery.
There is now a broad-based consensus among leading interventional radiologists that peripheral angioplasty using DCBs should be seen as a first-line revascularization option for both primary treatment and revision of advanced arterial occlusions in the SFA vascular territory. This will lead to better than 14% annual growth in these procedures through 2022.
#3 Transcatheter heart valve replacement.
The use of transcatheter techniques in heart valve replacement and repair is projected to grow at over 14%, to be supported by the anticipated regulatory approval of TAVR procedures for intermediate risk patients in late 2016, and, plausibly, for standard surgical risk caseloads by 2019.
#2 Left atrial appendage endovascular closure in AFib.
The global volume of endovascular LAA closure procedures is projected to experience a robust double-digit growth expanding an average of over 14% annually, nearly doubling to an estimated 52 thousand corresponding interventions in the year 2022. Anticipated strong growth in the endovascular LAA closure utilization will be driven by increasing penetration of the Asian-Pacific (primarily Chinese and Indian) market geography with an extra boost from the recent U.S. launch of transcatheter LAA closure systems. Advances in the mature European market and emerging ROW marketplace are likely to stay below projected average growth rates.
#1 Lower extremity angioplasty and DES procedures.
Lower extremity angioplasty and drug-eluting stenting is forecast to increase almost three-fold from 2016 to 2022.
From 2015 to 2022, the cumulative global volume of PTA procedures is projected to expand an average of 4.2% per annum to year 2022. The cited expansion will be driven largely by a strong annual procedural growth in the APAC region (primarily in China and India undergoing aggressive transition to modern interventional radiology practices), which is forecast to account for about over a third of PTAs performed worldwide in 2022. The U.S. and Western European geographies can be expected to register only a moderate PTA procedural growth to be supported mostly by increasing penetration of the SFA patient caseloads with DES-based interventions, but the worldwide utilization of stented PTAs (especially these employing DES devices) is forecast to grow at significantly faster (4.2% and 19.1%) average annual rates to over 986,000 and 203,000 corresponding procedures in the year 2022.