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Tracing the European course of cardiac resynchronization therapy from 2006 to 2008

Bela Merkely , Attila Roka , Valentina Kutyifa , Lucas Boersma , Antoine Leenhardt , Andrzej Lubinski , Ali Oto , Alessandro Proclemer , Josep Brugada , Panos E. Vardas , Christian Wolpert
DOI: http://dx.doi.org/10.1093/europace/euq041 692-701 First published online: 3 March 2010

Abstract

Cardiac resynchronization therapy (CRT) is a highly efficient treatment modality for patients with severe congestive heart failure and intraventricular dyssynchrony. However, the high individual cost and technical complexity of the implantation may limit its widespread utilization. The European Heart Rhythm Association (EHRA) launched a project to assess treatment of arrhythmias in all European Society of Cardiology member countries in order to have a platform for a progressive harmonization of arrhythmia treatment. As a result, two EHRA White Books have been published in 2008 and 2009 based on governmental, insurance, and professional society data. Our aim was to analyse the local differences in the utilization of CRT, based on these surveys. A total of 41 countries provided enough data to analyse years 2006–2008. Significant differences were found in the overall number of implantations and the growth rate between 2006 and 2008. Other contributing factors include local reimbursement of CRT, the existence of national guidelines, and a high number of conventional implantable cardioverter-defibrillator implantations, while GDP or healthcare spending has less effect. Focusing on improving these factors may increase the availability of CRT in countries where it is currently underutilized.

  • Cardiac resynchronization therapy
  • Europe
  • Reimbursement
  • Pacemaker
  • Implantable cardioverter-defibrillator

Introduction

The increasing incidence of congestive heart failure (CHF) is one of the major causes for the growing healthcare costs in industrialized countries. The overall CHF prevalence is ∼2%, which increases to 6–10% in the elderly population (age >65 years). The lifetime risk of developing CHF is ∼20%, regardless of gender,1 while the age-adjusted incidence of CHF remained stable over the past 20 years in Europe.2,3 Despite the advances of medical therapy, mortality is still high and quality of life is severely impaired in advanced stages.4 Using different measurements, the prevalence of mechanical dyssynchrony can reach 70% in patients with severe CHF.5

Cardiac resynchronization therapy (CRT) with atriobiventricular pacing (CRT-P) was introduced in the mid-90s and became increasingly popular after the promising results of the early trials.6,7 From the year 2000 onwards, implantable cardioverter-defibrillators capable of atriobiventricular stimulation became available (CRT-D). The convincing results first of large clinical trials and subsequently of meta-analyses formed the basis of evidence-based practice guidelines, published by professional societies, such as the European Society of Cardiology (ESC), European Heart Rhythm Association (EHRA), American Heart Association, American College of Cardiology, and the Heart Rhythm Society.811

Survey- and registry-based data regarding local pacing and electrophysiological practice, from several European countries are available12,13 and the EHRA launched a project to assess the treatment of arrhythmias in all ESC member countries in order to have a platform for a progressive harmonization of arrhythmia treatment. As a result, two EHRA White Books were published in 2008 and 2009 based on governmental, insurance, and professional society data.14,15

Methods

Data gathering

Data were gathered from the EHRA White Book publications.14,15 A total of 41 countries provided comprehensive data and were included in the analysis (Figure 1). It should be noted that demographic or economical data were dated a few years earlier in a few cases, but did not exceed 3 years. Implantation data from 2006, 2007, and 2008 have been analysed.

Figure 1

The 41 countries included in this analysis are Armenia, Austria, Belarus, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Egypt, Estonia, Finland, France, Georgia, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Latvia, Lebanon, Lithuania, Luxembourg, FYROM, Netherlands, Norway, Poland, Portugal, Romania, Russia, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Tunisia, Turkey, and UK (coloured in dark blue).

To gather data on the specific items a questionnaire was prepared. The questionnaire was presented and explained to the individual national representatives during the annual Spring Summit of the European Heart Rhythm Association in Nice 2007 and 2008. Each chairperson of the national working group of arrhythmias and/or pacing or president of the national society of arrhythmias was asked to provide data for each item. In many of the countries, national registry data, e.g. Spanish registry for catheter ablation were used as data source. In other countries, the president conducted a national survey or used reasonable estimates, if no exact data were available. Whenever estimates were used they were clearly indicated as such. Furthermore, data on ICD and pacemaker implantation were provided in parallel by EUCOMED (European Confederation of Medical Devices Association) for a number of countries. Data from EUCOMED were only used for entry into the White Book if the national chairman authorized the correctness of data for his country and only served as an additional source. In case no valid data were available, the data were not presented. For the presentation of the data of 2007, the most recent updated data were used from the 2009 edition. The same procedure was used both for the 2008 and 2009 edition. After the publication of the White Book, the national chairmen were asked to verify the data and to indicate mistakes. Only two mistakes were found and were immediately corrected in the published web version. The data collection and entry was performed by a Task Force of EHRA consisting of MBA students, EHRA staff, and members of the National Societies Committee.

Statistical analysis

For comparison, data are shown as mean ± standard deviation. Correlation analysis was performed by calculating Pearson's r. Stepwise multiple regression analysis was performed to identify independent factors that affect the number of CRT implantations per capita. The variables included were local CRT reimbursement, number of CRT centres per capita, availability of electrophysiology subspecialty, adherence to national or international CRT implantation guidelines, and healthcare spending per capita.

Results

Number of implantations

The number of CRT implantations per million capita for each country is shown in Figure 2. Table 1 lists the number of pacemaker, CRT, and ICD implantations in 2008 and the changes from 2006.

View this table:
Table 1

Pacemaker, ICD, and CRT implantation data 2006–2008

PM/mil pop 2008Change 2006–2008, PM/mil popDDD PM 2007 (%)CRT/mil pop 2008Change 2006–2008, CRT/mil popCRT-D% 2008ICD/mil pop 2008Change 2006–2008, ICD/mil pop
Armenia100.410.1n.a.11.54.78534.718.5
Austria922.532.26496.928.370134.125.0
Belarus161.5−1.6n.a.5.23.1504.13.6
Belgium833.1a−224.1an.a.n.a.n.a.n.a.153.828.8
Bulgaria335.632.2a1610.66.1a191.20.0a
Croatia482.257.4n.a.5.10.2918.56.7
Cyprus378.5n.a.n.a.n.a.n.a.n.a.44.2n.a.
Czech Republic821.9−27.655113.635.4a58196.970.7
Denmark737.9−1.36366.2−11.161228.8125.8
Egypt26.9n.a.n.a.1.3n.a.310.2n.a.
Estonia851.2142.27114.5−5.4513.82.3
Finland803.5154.2n.a.36.613.56331.5−50.0
France983.546.17584.015.161128.062.6
Georgia60.012.7291.30.41002.41.5
Germany1 193.416.967114.630.089262.269.5
Greece711.370.8n.a33.813.27593.155.0
Hungary470.720.65352.515.24254.316.8
Iceland896.9n.a.n.a.26.3n.a.38141.3n.a.
Ireland441.8a−104.7a48n.a.n.a.n.a.79.2a−45.5a
Israel456.8105.941115.659.285108.123.3
Italy1 054.3108.3n.a163.4b60.2b100b309.679.1
Latvia487.2126.0n.a.42.333.84316.99.4
Lebanon93.217.6n.a.25.2−7.69027.7−2.5
Lithuania561.8157.97416.010.9414.39.8
Luxembourg191.463.8n.a.20.64.14084.422.6
FYROM108.718.9n.a.5.8−6.3171.5−1.9
Netherlands648.862.2n.a.88.632.489194.587.7
Norway587.8a162.3a6851.2a5.0a43a126.8a56.4a
Poland707.8240.33734.823.66191.256.2
Portugal739.669.85541.810.47468.123.9
Romania105.515.9194.51.3244.81.8
Russia145.0a36.6a322.3a1.2a6a2.3a1.1a
Serbia461.32.7n.a.30.65.73031.312.4
Slovakia490.329.53037.623.380103.464.2
Slovenia547.927.9n.a.27.914.93447.89.0
Spain790.380.55343.110.37186.130.1
Sweden917.637.77094.026.34175.234.2
Switzerland710.745.56456.614.869155.598.4
Tunisia134.837.6587.95.5336.12.2
Turkey69.5a0.0an.a.6.3a1.4a33a12.5a1.4a
UK631.755.8n.a.77.120.56073.811.5
  • n.a., no data available.

  • aData from 2007.

  • bCRT-D only, no data for CRT-P.

Figure 2

Number of CRT implantations between 2006 and 2008.

Between 2006 and 2008, a comparison between the number of implantations for conventional pacemakers showed a relatively small increase. Only a few countries were able to significantly increase the rate by more than 100/million capita, namely Estonia, Finland, Israel, Italy, Latvia, Lithuania, Norway, and Poland. The ratio of dual-chamber pacemaker devices shows a great variation from as low as 16% in Bulgaria to as high as 75% in France.

The number of ICD implantations in 2008 also showed great variability: the highest was 310/capita in Italy. The increase in the number of implantations between 2006 and 2008 was more dramatic than for pacemakers, most prominently in Belgium, the Czech Republic, Denmark, Germany, Italy, the Netherlands, and Switzerland.

The highest CRT implantation rate in 2008 was in Italy with 163 CRT devices/million capita (CRT-D only, data on CRT-P are unavailable). The number of implantations grew most dramatically in Italy and Israel: an increase of 60 and 59 implantations/million capita in 2008 compared with 2006. The ratio of CRT-D to total CRT shows great variability between countries. The ratio was 100% only in Georgia, however, the total number of procedures was very low, just 0.4/million capita in 2008 (six implants in total). The ratio in most countries was <60%. The average number of CRT implantations/million capita for the 31 ESC countries which had data for all 3 year was 53 in 2006, 65 in 2007, and 76 in 2008, a 43.4% increase in just 2 years (population 518 million, excluded countries: Belgium, Bulgaria, Cyprus, Czech Republic, Egypt, Iceland, Ireland, Norway, Russia, and Turkey). Taking all 41 countries into account, using the last available year, if data from 2008 were missing, the total number of implantations was 42/million capita, total population 782 million, only Belgium excluded. In 2008, 70.9% of implanted devices were CRT-D and 29.1% CRT-P.

Economical, reimbursement, and medical-professional differences

Table 2 summarizes the gross demographic, economical, and insurance data. The health expenditure generally ranges between 7 and 10% of each country's income, the lowest ratio is in Armenia (4.7%), while the highest is in Switzerland (11.3%). The per capita healthcare expenditure shows great variability, mostly depending on the nation's per capita GDP: the lowest is in Egypt, 133 Euro/capita, the highest is in Luxembourg: 8499 Euro/capita. The proportion of the public insurance for the healthcare costs is generally between 60 and 80%, with several examples on both extremes: Croatia, the Czech Republic, Denmark, Iceland, Luxembourg, the Netherlands, Norway, Sweden, and the UK above 80%, while Armenia, Cyprus, Egypt, Georgia, Greece, Lebanon, and Tunisia significantly below 60%. The availability of general public insurance also shows significant variation. Only a few countries had no reimbursement for pacemakers, ICD, and CRT in 2008: Bulgaria, Croatia, Cyprus, Denmark, Egypt, Iceland, and the Former Yugoslav Republic of Macedonia (FYROM).

View this table:
Table 2

Demographic, economical, and insurance data

Pop, million 2008GDP, Euro/capitaHealth expenditure, Euro/capitaGovernment health expenditure (%)Public insurance (%)CRT reimbursement
Armenia2 968 586340116041.235Yes
Austria8 205 53352 15951647783Yes
Belarus9 658 768605838874.9100Yes
Belgium10 403 95149 430469671.190Yes
Bulgaria7 262 675684947359.863No
Croatia4 491 54314 414108180.190No
Cyprus792 60432 195202844.870No
Czech Republic10 220 91121 041143187.9100Yes
Denmark5 484 72367 387640284100No
Egypt81 713 517210913340.754No
Estonia1 307 60518 81094074.299Yes
Finland5 244 74954 578414878.576Yes
France64 057 79048 012532979.7100Yes
Georgia4 630 841306125721.525Yes
Germany82 369 54849 499514876.690Yes
Greece10 722 81633 434331042.589Yes
Hungary9 930 91516 343124270.8100Yes
Iceland304 36760 122559183.1100No
Ireland4 156 11964 660484978.332Yes
Israel7 112 35926 536207065.394Yes
Italy58 145 32140 450364077.1100Yes
Latvia2 245 42314 93089663.290Yes
Lebanon3 971 941737665646.860Yes
Lithuania3 565 20514 45689670100Yes
Luxembourg486 006118045849990.6100Yes
FYROM2 061 315468338471.690No
Netherlands16 645 31354 445506381.865Yes
Norway4 644 457102525892083.6100Yes
Poland38 500 69614 89392369.990Yes
Portugal10 676 91024 031240371.885Yes
Romania22 246 86299535677157Yes
Russia140 702 09412 57966763.20Yes
Serbia7 413 882705453671100Yes
Slovakia5 455 40718 585130173.975Yes
Slovenia2 007 71128 32823807385Yes
Spain40 491 05136 970299572.5100Yes
Sweden9 045 38955 624495181.2100Yes
Switzerland7 581 52067 379761460.334Yes
Tunisia10 383 577403221443.780Yes
Turkey71 892 807962974172.395Yes
UK60 943 91245 681383787.490Yes

The local differences in cardiac electrophysiological practice are significant (Table 3). Only Belarus, the Czech Republic, Egypt, Hungary, Latvia, the Netherlands, Poland, Portugal, Russia, Slovakia, Spain, and Tunisia recognized this field as an individual subspecialty. The number of CRT centres per capita is highest in Austria, 7.9/million capita, while most countries have between 1 and 2. The average number of CRT implantations per year for a centre is usually low, only the Czech Republic, Denmark, France, Israel, the Netherlands, Russia, Serbia, and the UK have more than 50 patients implanted per year. Most implants are now performed by cardiologists. Almost each country developed national PM/ICD guidelines and/or adheres to European or American guidelines, with the exception of Israel as of 2008.

View this table:
Table 3

Local practices in device therapy

EP subspecCRT centres/mil pop, 2008Average CRT/centre/-yearCRT implantation by cardiologists (%)National PM/ICD guidelinesUS/Euro PM/ICD guidelines
ArmeniaNo0.334.0100NoYes
AustriaNo7.912.235NoYes
BelarusYes0.225.00YesYes
BelgiumNo3.4n.a.95YesYes
BulgariaNo0.812.887.5NoYes
CroatiaNo0.95.880NoYes
CyprusNo2.5n.a.100NoYes
Czech RepublicYes1.577.480YesNo
DenmarkNo1.351.9100YesNo
EgyptYes0.118.050YesYes
EstoniaNo1.59.576NoYes
FinlandNo1.524.095YesYes
FranceNo1.363.3100YesYes
GeorgiaNo0.62.0100NoYes
GermanyNo4.0a28.4a45YesYes
GreeceNo1.325.999NoYes
HungaryYes1.243.493YesYes
IcelandNo3.38.050NoYes
IrelandNon.a.n.a.n.a.YesYes
IsraelNo1.768.595NoNo
ItalyNo6.9a23.8a99YesYes
LatviaYes0.947.560YesYes
LebanonNo2.510.0100NoYes
LithuaniaNo0.819.0100NoYes
LuxembourgNo2.110.0100NoYes
FYROMNo0.512.0100NoYes
NetherlandsYes1.086.899YesYes
NorwayNo2.6a19.8a100NoYes
PolandYes1.425.799NoYes
PortugalYes2.021.299NoYes
RomaniaNo0.49.9100NoYes
RussiaYes0.053.370YesYes
SerbiaNo0.556.8100NoYes
SlovakiaYes1.134.2100YesYes
SloveniaNo1.028.095NoYes
SpainYes0.947.198YesYes
SwedenNo2.438.698YesYes
SwitzerlandNo2.919.599YesYes
TunisiaYes0.810.3100NoYes
TurkeyNo0.318.0100NoYes
UKNo0.988.7100YesNo
  • The two right columns indicate adherence to local or international device guidelines. In case of missing data the field was left blank.

  • aData from 2007.

Factors affecting the number of CRT implantations

The number of CRT implantations and the growth between 2006 and 2008 is higher in countries, where the devices are reimbursed or who adhere to a national guideline (Table 4).

View this table:
Table 4

Analysis of factors affecting CRT implantations

CRT/mil pop 2008Change 2006–2008, CRT/mil popCRT-D of total CRT, 2008
CRT reimbursement
 Yes48.5 ± 41.248.0 ± 80.856.6 ± 27.2%
 No19.2 ± 24.626.8 ± 24.629.0 ± 18.8%
EP subspeciality
 Yes39.3 ± 34.661.3 ± 72.453.2% ± 23.8%
 No46.0 ± 43.139.4 ± 79.151.8% ± 29.9%
National guideline
 Yes63.5 ± 43.825.6 ± 85.259.6 ± 23.4%
 No28.0 ± 29.563.9 ± 65.546.2 ± 30.1%
European or US guideline
 Yes38.1 ± 37.847.2 ± 79.350.6 ± 28.7%
 No93.1 ± 25.233.2 ± 59.765.9 ± 12.9%
% DDD PMr = 0.457r = 0.165r = −0.023
ICD/mil popr = 0.843r = −0.082r = 0.569
GDP/capitar = 0.410r = 0.028r = 0.188
Health/capitar = 0.468r = −0.013r = 0.257
Gov cost (%)r = 0.427r = 0.049r = −0.186
Publ ins (%)r = 0.350r = 0.220r = −0.100
CRTcentre/mil popr = 0.657r = 0.016r = 0.401
Avg impl/CRT centrer = 0.517r = −0.101r = 0.238
CRT by cardiologistr = 0.023r = 0.093r = 0.111
  • Data for dichotomous variables are shown as mean ± standard deviation. Pearson's correlation coefficient (r) was calculated for scale variables.

While countries with higher GDP or healthcare spending per capita generally had a higher number of implantations, due to large variations the correlation between these factors and the number of CRT implantations was weak. There is stronger correlation between per capita CRT implantations and the number of ICD implantations (Figure 3, Table 4). Similarly, the ratio of dual-chamber pacemaker implantations, the general availability of governmental or public insurance, or cardiologist-performed procedures have minimal or no correlation with the number of CRT implantations. Both the growth of CRT implantations and the higher ratio of CRT-D correlated mostly with the number of ICD implantations (Table 4).

Figure 3

The number of CRT implantations correlates well with the number of ICD implantations (top), but not with total GDP (middle) or healthcare spending (bottom). All numbers are per capita. GDP and healthcare spending is in Euro.

Multiple regression analysis showed that the number of CRT implantations per capita was significantly affected by local CRT reimbursement (P = 0.023), number of CRT centres per capita (P < 0.001), adherence to national guidelines (P = 0.002), and adherence to European or US guidelines (negative effect, P < 0.001). Accredited electrophysiology subspecialty and healthcare spending per capita were not significant factors (P = 0.668 and P = 0.899, respectively). As of note, only a very few countries, each one with a high implantation rate, indicated that they follow national guidelines only (Czech Republic, Denmark, UK; Israel denied both).

Discussion

Cardiac resynchronization therapy with or without a defibrillator is a class I recommendation with a level of evidence ‘A’ for patients with left ventricular systolic dysfunction (ejection fraction <35%), symptomatic heart failure despite optimal medical therapy, and a QRS duration of ≥120 ms, in order to improve survival and reduce morbidity.10 Based on the great difference in the number of implantations between the countries, it is likely that many patients who would potentially benefit from device therapy do not receive it. On the other hand, there are data that some patients who receive a CRT do not fulfil all the guideline criteria.16 As guidelines do not necessarily conform strictly to the entry criteria for clinical trials (for instance, the ESC guidelines do not exclude patients with atrial fibrillation), substantial variations in implantation routines may exist, based on economical factors or individual experience. The EHRA and the Heart Failure Association initiated the European CRT survey in 2009 to describe the current European practice and routines associated with CRT implantations-based sampling in 13 countries. The survey analysed demographics and clinical characteristics, diagnostic criteria, implantation routines and techniques, short-term outcomes, adverse experience, and assessment of adherence to guideline recommendations.17 It has showed that approximately one-fourth (23%) of the patients had atrial fibrillation and one-fourth of them (26%) had had a device implanted previously. Thirty-one percent of the patients were older than 75 years. Altogether 22% of the patients were in NYHA functional class I or II. In conclusion, the survey data showed that general practice do not adhere to the guidelines strictly and there are major differences with regard to the proportion of elderly patients, presence of atrial fibrillation, or a previous device as compared with the randomized clinical trials. However, long-term data are needed to evaluate the response to the therapy in this patient population.

There is no easy way to tell what number of CRT implantations would be optimal. With current implantation indications, up to 30% of patients are non-responders, while other patients, who could potentially benefit, may not be included. The surveys initiated by ESC and its associated organizations will provide detailed data on the epidemiology of CHF and potentially eligible patients.

Clarification of the indications is the subject of several ongoing or recently finished trials.18,19 The MADIT-CRT trial has shown the effect of CRT in NYHA I, II class patients.20 Recent publications suggest that patients with a left ventricular ejection fraction of up to 40% and with few or no symptoms may also benefit from CRT.21 The deleterious effects of chronic right ventricular stimulation have long been identified.22 Currently a large number of patients with bradycardia indications receive conventional pacemakers and are at risk of developing pacing-induced dyssynchrony and CHF. Initial data are promising that a ‘CRT upgrade’ in this population can be similarly effective as with patients with conventional CRT indications.23 The BIOPACE clinical trial investigates the use of CRT in high-degree AV block in a general population.24 In the case of a positive outcome, the number of patients eligible for CRT may increase significantly, similar to the sudden increase in ICD implantations when the results of primary prevention trials were incorporated into guidelines. However, in addition to the cost, the high complexity of CRT implantation and the relatively low number of procedures per centre, with lack of experience (possibly also because of the low number of EP subspecialists) may also limit the number of implantations.

The issue of cost-efficiency of CRT has been addressed in several papers.18,19 CRT-P appears a highly cost-effective addition to medical therapy among eligible patients. CRT-D is cost-effective when there is a reasonable life expectancy at the time of implantation. CRT was shown to be cost-effective even in the ninth decade.19 The question whether CRT-D or CRT-P will be more cost-efficient in a given patient group will need to be determined in future studies. Cost-efficiency data are essential to convince the local healthcare insurers to reimburse CRT, and this seems to be a major factor describing the differences between European countries.

Implantation of a transvenous CRT device is a technically demanding task which requires significant expertise and may require new invasive methods to apply.25 All the large randomized clinical trials (COMPANION, CARE-HF, REVERSE) showed a failure rate to implant the device of 5–10%.2628 European data show that having an accredited electrophysiology subspecialty only has a very modest effect on the number of CRT implantations. This may be due to different requirements for certification or high number of implantations performed by non-electrophysiologists even when such a subspecialty exists in a country. More studies will be needed to investigate this finding.

In addition, the number of CRT devices implanted per centre may highly influence the success rate. Beyond reimbursement, the fact that the number of CRT implantations have a better correlation with ICD implantations than with financial indicators like GDP or healthcare spending, may suggest that the limitations for widespread utilization of CRT are mainly technical and not economical (physicians who can perform ICD implantations may also consider implanting CRT-D when indicated). Therefore, the education of device therapy treatment and the implantation procedure has to be focused upon to increase the number of implantations. European standards such as the EHRA individual accreditation in Cardiac Pacing and ICDs (and CRT) may help this process. The aim is to ensure an equal access to this highly efficient and cost-effective treatment and to have CRT devices implanted by qualified electrophysiologists in all European countries.

Limitations

The EHRA White Book survey was not able to provide complete data for all 51 ESC countries. The data represent a reasonable percentage of the actual procedures but certainly not the absolute reality, since even the best national or international registries do not cover 100% of the interventions. However, the correctness of data were authorized by each national chair or president and in case of estimates, they are very close to what can be expected. Benchmarking testing had not been conducted. There has been no negative feedback over the last 2 years after publication of the White Book, although there is open access to the data. There were no indications of mistakes or changes by national societies during the last 2 years, which makes us confident that the data represent each country's reality at best.

Conclusion

The joint effort of the ESC and EHRA highlighted the significant variation in local utilization of CRT. These differences might not only be explained by the unequal financial realities of the countries, but also by variations in reimbursement and guideline adherence.

Funding

The whole EHRA White Book project was made possible by an unrestricted educational grant from Biotronik GMBH, Berlin, Germany. The article has been granted an unrestricted educational grant of TÁMOP (Social Renewal Operative Program) 4.2.2.-08/1/KMR (National Development Agency, Hungary).

Conflict of interest: Biotronik GMBH provided funding for the project.

References

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