Evaluation of the UK Intervention Subspecialty Programme: The Trainees’ Experience

Interventional cardiology (IC) is a competitive and oversubscribed subspecialty, requiring trainees to master numerous techniques over a 2-year fellowship. In 2022, the Joint Royal Colleges of Physicians Training Board instituted a complete curriculum change for all UK medical specialty training programmes.¹ This new curriculum mandates dual accreditation in general internal medicine (GIM) to support ever-increasing demand, and to prepare the next generation for a multimorbid, ageing population.²

IC remains the most popular of five subspecialties that UK trainees can select after completion of 3 years of general cardiology. Other notable changes to the new curriculum include further general cardiology exposure in subspecialty years, and a themed third year of registrar training based on a trainee’s subspecialty of interest. Trainees who had already started training in cardiology were given the option to opt out of curriculum transition and complete single accreditation on the 2010 curriculum.³

This survey was designed to provide a snapshot of UK cardiology training at this pivotal time, prior to all trainees being established on the 2022 curriculum.

Methods

The survey ran from November 2023 to March 2024. It was designed for UK subspecality intervention trainees, including those on the 2010 curriculum and 2022 curriculum. To avoid possible confusion in terminology, trainees are henceforth referred to as first and second subspecialty year trainees, given the change in specialty training number. 2010 dual accrediting trainees who subsequently used an ST8 year will be referred to as third-year trainees. Post Certificate of Completion of Training (CCT) fellows who completed the UK training programme were eligible. Those who held subspecialty training posts and were conducting out of programme research/experiences were also eligible.

The survey was prepared using SurveyMonkey and included 68 questions (Supplementary Appendix). It was distributed through the British Cardiovascular Intervention Society (BCIS) mailing list, as well as via email to training programme directors. Questions included first-operator percutaneous coronary intervention (PCI) numbers, exposure to adjunct techniques and confidence in becoming a consultant. Categorical data are presented as counts (and percentages), continuous data as mean ± SD or median [interquartile range] depending on the normality of distribution. Statistical analysis was performed using RStudio Version 2023.12.1 (Posit) and GraphPad Prism 9.

Presubspecialty trainees who completed the survey were excluded from the analysis. Any respondents who failed to complete >75% of the survey were also excluded.

Results

Survey Demographics

Participants

In total, 106 responses were received, 46 of which were excluded from the analysis (Supplementary Figure 1). The geographical representation of responders is shown in Supplementary Table 1. Determining the exact number of intervention training registrars nationally was challenging due to the lack of a centralised record. Through communication with training programme directors, we estimated 125 intervention subspecialty posts, including out-of-programme trainees. Based on this figure, the completion rate for training grades was 38%.

Demographics

The majority of participants were in the 35–39 years age group (Figure 1). A total of 87% were men, which is in line with the current data on sex disparity within the specialty (and subspecialty).⁴

Training Curriculum

The distribution of participants across different curricula and grades are shown in Figure 1.

Of the 2010 cohort, six (12%) chose to dual accredit in GIM. For the 2022 cohort, GIM accreditation is mandatory, meaning a total of 30% of fellows are currently dual training.

Academic Experience

A total of 65% of the cohort had either completed a research degree or were currently doing so, with an even split between MD/PhD. Four trainees were academic clinical lecturers on the dual clinical–academic pathway.

Procedural Numbers and Training Time

Training Time

The mean amount of cath lab time for training grades was 51 ± 21% of the working week. The mean lab time for post-CCT fellows only was 57 ± 21% of the week.

Percutaneous Coronary Intervention Numbers

A breakdown of PCI numbers is displayed in Figure 2. The total number of first-operator PCI procedures performed by participants across different grades is shown in Table 1. This is the total procedural number to date at the time of the survey, which was conducted in the second quarter of the training year.

Trainees who had completed at least 1 year of subspecialty training were asked how many first-operator PCI they had undertaken in their first training year (Supplementary Table 2). The median number of first operator cases across both curricula in first year was 101–200. For the 2010 curriculum trainees, 52% of trainees did not achieve >200 first-operator PCI in their first year (Figure 2).

For second-operator PCI, 38% of trainees had 201–400, with a further 28% having 401–600 PCI (Supplementary Table 3).

Other Procedures

After adjusting for outliers, the number of temporary pacing wires was six [interquartile range 5–10], and number of pericardiocentesis procedures was six [interquartile range 3–7.25].

Vascular Access Techniques

Regarding access, 98% of trainees felt confident in radial access and 62% with femoral access, with a further 17% somewhat comfortable. Femoral access confidence increased with seniority. Trainees estimated that 10% of their cases involved femoral access.

A total of 95% of trainees felt confident or somewhat comfortable using ultrasound to assist in vascular access, but only 70% of trainees reported using it for almost all (>90%) femoral access. The majority (75%) of trainees stated they rarely used ultrasound in radial access (never: <10% of cases).

Use of micropuncture kits for femoral access was variable; 28% had not been trained with this technique, while 22% stated they used this in almost all femoral access (>90%). Regarding vascular closure, 93% of participants were comfortable using Angio-Seal devices (Terumo), 23% were comfortable using a Proglide (Abbott) and just two trainees reported being comfortable using the MANTA device (Teleflex).

Coronary Physiology

A large variation in confidence was seen in undertaking coronary physiology between training grades (Supplementary Figure 2), with 33% of first-year and 58% of second-year trainees feeling confident in hyperaemic techniques.

A total of 72% of trainees felt they had adequate exposure to training in coronary physiology. The cited reasons for those who felt unprepared include a lack of formal teaching and insufficient local exposure to microvasculature assessments.

Calcium Modification

Confidence among calcium modification devices was variable. The majority of trainees had not been trained in orbital atherectomy (64%) or excimer laser catheter atherectomy (81%). Only 5% of trainees felt confident in rotational atherectomy (RA), with a further 23% somewhat comfortable. This translated to RA procedural numbers for second- and third-year trainees being zero to five; this remained the case for post-CCT fellows.

A total of 65% of trainees felt confident using intravascular lithotripsy (IVL), with a further 18% somewhat comfortable. The median number of procedures using IVL for second years and above was 11–20. Confidence using OPN high-pressure balloons was variable, with 33% at least somewhat comfortable and a further one-third with no exposure to the technique (Figure 3).

A total of 54% of trainees felt they had inadequate exposure to training in calcium modification. Cited reasons were technology availability and trainer belief that use of atherectomy devices is a post-CCT skill.

Intracoronary Imaging

More trainees reported feeling confident or somewhat confident using intravascular ultrasound (82%) than optical coherence tomography (53%; Figure 4). The median number of intravascular imaging (IVI) cases that trainees had participated in was 76–100, with first-operator cases being 51–75. Overall, 70% of trainees felt they had adequate exposure in training to IVI. For those with inadequate exposure; barriers cited were optical coherence tomography availability, senior reluctance to use imaging and lack of time in cases for interpretation training.

Bifurcation Technique

Supplementary Figure 3 displays the breakdown in confidence levels and case numbers for each bifurcation technique. Most trainees felt confident with a provisional stenting technique (65%), with the median number of cases being 21–30. A total of 23% were confident with a culotte technique, 17% with a double-kissing crush, and 15% with T- and small protrusion/T-stent variants. The median number of cases performed using a two-stent technique was 11–20.

A total of 42% had received simulation training in bifurcation techniques. The feedback indicated that this training was very useful, especially when particularly wet models were available.

Complication Management

The proportion of IC fellows who were confident with covered stents was 10%, coils 5%, snares 2%, fat emboli 0%, simple thrombectomy 67%, intra-aortic balloon pump 42% and management of no reflow 43%. Coils, snares and fat emboli were reported as difficult techniques to achieve training in, with 40% of trainees having no experience in these modalities.

The median number of major complications all respondents were involved with was 0–10; this was similar across grades. A total of 33% of trainees had received formal training in complication or crisis management in cath lab procedures, 28% had received training in human factors related to the cath lab environment and a further 40% had received general human factors training. Trainees who had received this training stated it was very useful and covered key concepts, such as task perseverance and operating under stress.

Structural Intervention

Training in structural procedures is not currently included in either training curriculum. Despite this, 38% of trainees report wishing to pursue a career in structural intervention, with the median number of structural cases that trainees have assisted with being one to five. The majority of trainees interested in pursuing structural intervention made this decision during their subspecialty posts. Limited exposure and the requirement for further training extension were listed as discouraging factors for pursuing structural intervention.

Learning Resources

The most preferred learning resources were conferences, the BCIS training course and webinars (Supplementary Figure 4). Regarding areas inadequately covered by existing training, feedback included complications and simulation training in complex techniques, such as two stent bifurcation and calcium modification.

Radiation

A total of 85% of respondents stated they check their radiation doses <50% of the time. Additionally, 68% of participants stated they do not keep track of their monthly or annual radiation dose. The primary barriers to maintaining such records were identified as a lack of personal motivation and the belief that it was not their responsibility. To reduce radiation risk, respondents mentioned several measures, including the use of protective equipment, such as lead aprons and shields, minimising screening time and using tools, such as RadPad.

Overall Experience of the Programme

A total of 17% of trainees reported finding the training programme very stressful, with a further 63% finding it somewhat stressful. The commonest reasons included amount of service provision and difficulty accessing the lab. A total of 78% felt that they had adequate pastoral support, but many felt they would benefit from one-to-one mentorship.

A total of 50% felt that they would not be ready to be an interventional consultant after completion of the training programme; the main reason behind this was lack of procedural experience. A total of 65% stated they plan to extend training by undertaking a fellowship, 10% planned to extend/repeat a subspecialty year and a further 10% were planning on extending with a post-CCT grace period.

Overall, 25% rated the programme as excellent, 47% good, 18% average and 10% poor. The primary issues identified were a lack of lab time and opportunities to develop procedural skills, both being restricted by service provision. Even among those with a positive overall experience, concerns about insufficient procedural volume and the development of more complex skill sets were common.

Discussion

The survey aimed to assess UK trainees’ experience of the training programme, and evaluate whether the current system meets their needs. With 22% of respondents migrating to the 2022 curriculum, UK cardiology training is clearly in a transitional phase. The updated curriculum retains similar requirements, but now mandates all GIM competencies within the same timeframe, raising concerns about its impact on procedural subspecialties, such as IC.^5,6

Both training schemes are competency based, recognising that technical ability varies among individuals. There is no defined number of first-operator PCIs required to achieve programme sign-off. Despite this, procedural numbers are often used as an overall marker of competence and to evaluate training posts. Prior BCIS guidance from 2015 recommended a minimum of 200 procedures/year over the 2 years prior to consultant appointment, with at least 125 as the first operator.⁷ The US guidance recommends that fellows should perform a minimum of 250 coronary interventions per year.⁸

Our data suggest that the prior UK guidance may be outdated. Most UK trainees surpass these numbers, yet seek additional training to refine their skills. We recommend that trainees aim for a minimum of 400 first-operator PCI cases during their 2-year interventional fellowship, which has been outlined in the new BCIS 2025 PCI guidelines.⁹ The initial caseload should focus on developing fundamental technical skills, with the latter half allowing trainees to cultivate independent decision-making. Second-operator PCI also plays a critical role, particularly after basic skills are established, as it provides invaluable exposure to complex decision-making. Ultimately, as long as trainees are progressing well, the quality of cases handled in the second year is likely more important than quantity.

Mastering arterial access, interpretation of coronary physiology and the use of IVI are core skills that are fundamental to interventional fellowship training.^10–15 Familiarity with these skills should be developed within the first year, to align with evolving practice in the UK. Independence in femoral access will take longer, as it comprises just 10% of the current caseload, but remains essential. There are certain areas that could still be improved; for example, significant evidence supports the use of ultrasound to reduce vascular complications, and it should be considered mandatory for femoral access.¹⁶ Micropuncture kits also reduce vascular complications, and further training in this technique is desirable.¹⁷

Confidence in interpreting hyperaemic and non-hyperaemic techniques is high, although competence in microvascular assessment is lagging, likely due to geographic variability and limited exposure. IVI, which improves outcomes and is a class 1A recommendation for complex lesions, remains a critical focus.^14,18–21 More emphasis is also needed to advance optical coherence tomography training.

Radiation safety is also critical, essential for mitigating malignancy risks.^22,23 Despite advances in protective equipment, adoption across UK centres is inconsistent, and challenges remain in radiation dose tracking, particularly for trainees rotating between hospitals. While basic safety measures are well understood, tools, such as immediate dosimeters, are underutilised, highlighting the need for improved awareness and implementation.²⁴

The management of complex lesion subsets, such as calcific disease and bifurcation PCI, typically develops in the later stages of interventional training. These procedures carry a higher risk of complications and often require advanced tools for calcium modification, such as IVL and RA.^25,26 IVL has become a widely adopted technology and is generally well-received by trainees, with the majority reporting comfort with its use. In contrast, comfort in RA was significantly lower, with procedural numbers being notably limited. The rise of IVL has coincided with a decline in RA cases in the UK, reducing use among trainers and, therefore, limiting training opportunities. These factors, alongside procedural complexity, intricate equipment and the need for well-established PCI skills, are likely to contribute to low volume and lack of confidence among trainees. Additionally, several respondents commented that RA is regarded as a post-CCT skill, which suggests there may be a mismatch in trainee and trainer perception of required competencies by the end of training.

The UK 2022 curriculum does little to bridge this gap, providing only broad guidance for competencies in IC training. For example, with regard to RA, it simply states complex PCI, including calcific disease, should be performed using appropriate adjunctive technology. In contrast, the European Association of Percutaneous Cardiovascular Interventions core curriculum states that the minimum requirement is performance as second operator and/or with direct supervision after 2 years of training.²⁷ Clearer guidance within the UK curriculum would align expectations and provide better-defined benchmarks for both trainees and trainers.

Learning does not stop at CCT, and advanced skills can be refined throughout consultancy, often through proctorship. Given that complication scenarios are thankfully rare, we recognise that complete confidence in managing such cases may never be achieved, even with several years’ experience. However, it is notable that few trainees felt confident using covered stents or coils. One method of improving exposure to all of these complex modalities is simulation and human factors training, which received extremely positive feedback.

IC training is demanding, but rewarding. Our survey highlighted many found it stressful, a sentiment echoed by feedback from US fellows.²⁸ However, despite the challenges, the majority of UK trainees reported enjoying their training experience. Unfortunately, the transition from trainee to consultant is fraught with uncertainty. Despite having the longest training programme worldwide, half of the respondents felt unprepared to assume consultant roles upon completion of their training.²⁹ A total of 75% expressed the need for further training through fellowships or additional years, underscoring a gap between positive training experience and readiness.

This gap stems in part from critical shortcomings in the system. Many point to the lack of procedural opportunities and the discomfort in managing complex cases as significant barriers. These challenges are compounded by increasing service demands on an already overburdened healthcare system, which leaves less room for hands-on training. The introduction of the 2022 curriculum, which adds GIM commitments during the final training year, threatens to exacerbate these issues. If procedural volume is already inadequate for single-accrediting trainees, how can we expect a general physician, general cardiologist and interventional cardiologist to emerge from the same programme fully equipped?

Unfortunately, there are no straightforward solutions. Options include increasing the number of trainees to alleviate service pressure, but risk diluting procedural opportunities, or allowing subspecialisation earlier in the training programme. Furthermore, a more clearly defined curriculum outlining specific technical competencies could help, by setting realistic goals for both trainers and trainees.

With regard to GIM, as the impact of the 2022 curriculum unfolds, it will be crucial to monitor outcomes. If it becomes evident that craft skills training has been further eroded, then reassessment of the requirement for mandatory GIM accreditation will be required, or, at a minimum, the enforcement of GIM in the later stages of training. Other healthcare systems, such as those in North America, adopt different training models allowing GIM accreditation before specialty training, keeping the two separate.³⁰ While this approach could address some of the aforementioned issues, it is vastly different from the UK system, and would require a complete overhaul of medical specialty accreditation in the UK – an unrealistic prospect.

Structural heart disease intervention represents yet another area of urgent need. Encouragingly, over one-third of trainees expressed an interest in the field. Transcatheter interventions for structural heart disease are a rapidly growing field within IC across the world, including the UK.³¹ Yet, structural intervention training remains conspicuously absent from the UK curriculum, leaving trainees to pursue this expertise through post-CCT fellowships. The consequences are clear: limited exposure during training and the potential of unmet demand for structural interventionists in the face of a growing population need. Whether through curriculum reform or a dedicated credentialing process, the field of structural intervention requires attention.

This study had some limitations. The survey included 60 participants, leading to an underpowered study for detecting significant differences. We estimate the completion rate was 38%, indicating potential selection bias. The southwest (Severn/Peninsula) and northwest (Mersey/North West) deaneries were underrepresented. Furthermore, the survey launched in November, which is approximately one-quarter of the way into the training year. Thus, the reported figures represent only those collected to this point, rather than the total anticipated by year’s end. In addition, these data are self-reported, so they may be subject to response bias.

Conclusion

In this landscape of expanding specialisation within cardiology and the drive for generalisation in healthcare nationally, the future of IC training requires both innovation and adaptation. Addressing these issues will be critical not only for trainees, but for the patients who will rely on their expertise in years to come.

The UK training programme has strengths, including strong trainee experience, pastoral support and solid foundational exposure; however, a key shortcoming is the need for most trainees to extend their training before reaching consultancy. Simulation training may help bridge the gap for training opportunities in certain techniques, particularly when case exposure is limited.

Moving forward, monitoring the impact of the 2022 curriculum on IC training will be essential. The insights from this survey will inform ongoing improvements, guide future reforms and help identify topics for future training days.

Click here to view Supplementary Material and Supplementary Appendix.