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Granfeldt, Hans
Publications (10 of 34) Show all publications
Sundbom, P., Roth, M., Granfeldt, H., Karlsson, D., Ahn, H. C., Gustafsson, F. & Hübbert, L. (2018). Sound analysis of a left ventricular assist device: A technical evaluation of iOS devices. International Journal of Artificial Organs, 41(5), 254-260
Open this publication in new window or tab >>Sound analysis of a left ventricular assist device: A technical evaluation of iOS devices
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2018 (English)In: International Journal of Artificial Organs, ISSN 0391-3988, E-ISSN 1724-6040, Vol. 41, no 5, p. 254-260Article in journal (Refereed) Published
Abstract [en]

Introduction: The use of left ventricular assist device (LVAD) has grown rapidly. Adverse events do continue to occur. In recent years, analysis of LVAD sound recordings emerged as a means to monitor pump function and detect pump thrombosis. The aim of this study was to characterize the sounds from HeartMate II and to evaluate the use of handheld iOS devices for sound recordings. Method: Signal analysis of LVAD sound recordings, with dedicated recording equipment and iOS devices, was performed. Two LVADs running in mock loop circuits were compared to an implanted LVAD. Spectral analysis and parametric signal models were explored to quantify the sound and potentially detect changes in it. Results: The sound recordings of two LVADs in individual mock loop circuits and a third one implanted in a patient appeared to be similar. Qualitatively, sound characteristics were preserved following changes in pump speed. Recordings using dedicated equipment showed that HeartMate II sound comprises low-frequency components corresponding to pump impeller rotation, as well as high-frequency components due to a pulse width modulation of the electric power to the pump. These different signal components interact and result in a complicated frequency spectrum. The iPhone and iPod recordings could not reproduce the sounds as well as the dedicated equipment. In particular, lower frequencies were affected by outside disturbances. Discussion: This article outlines a systematic approach to LVAD sound analysis using signal processing methods to quantify and potentially detect changes, and describes some of the challenges, for example, with the use of inexpensive recording devices.

Place, publisher, year, edition, pages
SAGE PUBLICATIONS LTD, 2018
Keywords
HeartMate II; left ventricular assist device; sound; spectral analysis
National Category
Biomedical Laboratory Science/Technology
Identifiers
urn:nbn:se:liu:diva-148111 (URN)10.1177/0391398818762352 (DOI)000432135400004 ()29519192 (PubMedID)
Available from: 2018-05-30 Created: 2018-05-30 Last updated: 2019-05-01
Vikholm, P., Ivert, T., Nilsson, J., Holmgren, A., Freter, W., Temstrom, L., . . . Friberg, Ö. (2018). Validity of the Swedish Cardiac Surgery Registry. Interactive Cardiovascular and Thoracic Surgery, 27(1), 67-74
Open this publication in new window or tab >>Validity of the Swedish Cardiac Surgery Registry
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2018 (English)In: Interactive Cardiovascular and Thoracic Surgery, ISSN 1569-9293, E-ISSN 1569-9285, Vol. 27, no 1, p. 67-74Article in journal (Refereed) Published
Abstract [en]

OBJECTIVES: Our goal was to validate the Swedish Cardiac Surgery Registry by reviewing the reported cardiac operations to assess the completeness and quality of the registered data and the EuroSCORE II variables. METHODS: A total of 5837 cardiac operations were reported to the Swedish Cardiac Surgery Registry in Sweden during 2015. A randomly selected sample of 753 patient records (13%) was scrutinized by 3 surgeons at all 8 units in Sweden performing open cardiac surgery in adults. RESULTS: Coverage was excellent with 99% [95% confidence interval (CI) 98-99%] of the performed procedures found in the registry. Reported waiting times for surgery were correct in 78% (95% CI 76-79%) of the cases. The main procedural code was correctly reported in 96% (95% CI 95-97%) of the cases. The correlation between reported and monitored logistic EuroSCORE II had a coefficient of 0.79 (95% CI 0.76-0.82), and the median difference in EuroSCORE II was 0% (interquartile range -0.4% to 0.4%). The majority of EuroSCORE II variables had good agreement and coherence; however, New York Heart Association functional class, preoperative renal dysfunction, left ventricular ejection fraction, Canadian Cardiovascular Society Class IV angina and poor mobility were less robust Postoperative complications were rare and in general had a high degree of completeness and agreement. CONCLUSIONS: The reliability of the variables in the national Swedish Cardiac Surgery Registry was excellent. Thus, the registry is a valuable source of data for quality studies and research. Some EuroSCORE II variables require improved and stricter definitions to obtain uniform reporting and high validity.

Place, publisher, year, edition, pages
OXFORD UNIV PRESS, 2018
Keywords
Swedish Cardiac Surgery Registry; Validation; New York Heart Association functional class; EuroSCORE
National Category
Surgery
Identifiers
urn:nbn:se:liu:diva-149863 (URN)10.1093/icvts/ivy030 (DOI)000438341400011 ()29452368 (PubMedID)
Available from: 2018-08-02 Created: 2018-08-02 Last updated: 2019-05-02
Sundbom, P., Ahn, H., Kornhall, B., Loebe, M. & Granfeldt, H. (2014). (556) – Change in Acoustic Fingerprints at Increased Pump Speed During Echocardiographic Ramp Test. In: : . Paper presented at 34th Annual Meeting and Scientific Sessions of the International-Society-for-Heart-and-Lung-Transplantation (pp. S206). Elsevier, 32(4S)
Open this publication in new window or tab >>(556) – Change in Acoustic Fingerprints at Increased Pump Speed During Echocardiographic Ramp Test
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2014 (English)Conference paper, Poster (with or without abstract) (Refereed)
Abstract [en]

Purpose

The continuous flow mechanical circulatory support HeartMate II (Thoratec Corporation, Inc. Pleasanton, USA) (HMII), generates an auditory signal (acoustic fingerprint) that can be registered by routine auscultation. A temporary or permanent change in sound indicates a change in pump function. Previous mock loop studies have shown that changes in acoustic fingerprint are due to changes in speed, so the aim of this study was to see if the acoustic fingerprint changed during an echocardiographic ramp test.

Methods

Four stable, event-free patients included in the SoundMate study performed an echocardiographic ramp test. The speed was increased stepwise by 400 rpm between 8 000 and 12 000 rpm, and the left ventricular end diastolic diameter, flow, power consumption and blood pressure were measured. Sounds from HMII were recorded using an iPhone™ (Apple Inc. Cupertino, CA, USA) with the stethoscope application iStethPro™ (Dr. Peter J Bentley, UK) and the frequency map analyzed using the Audacity™ program (Unicode, Ash, Chinen and Crook, USA). The acoustic fingerprint is divided into regions (R1: 1 000-6 500, R2: 8 500-14 000, R3: 15 000-21 000 Hz) and peaks (P1: 0-1 000, P2: 6 500-8 500, P4: 21 000-23 000 Hz) in order to facilitate calculations and clarify changes in frequency.

Results

There were significant (p<005) changes in the acoustic fingerprint when increasing the pump speed between 8 000 and 12 000 rpm. In 2/4 patients there were no significant changes in P1, otherwise there were significant changes in all regions and peaks. During the ramp test the power increased in mean 7 W, flow 3,1 L/min and the blood pressure measured with Doppler increased by ~15 mmHg. The left ventricular size decreased with ~2 cm.

Conclusion

The acoustic fingerprint changes with pump speed. This implies that when using sound check for detection of pump dysfunction, a new baseline should be set after every adjustment of speed.

Place, publisher, year, edition, pages
Elsevier, 2014
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-114003 (URN)10.1016/j.healun.2014.01.898 (DOI)000333866700557 ()
Conference
34th Annual Meeting and Scientific Sessions of the International-Society-for-Heart-and-Lung-Transplantation
Available from: 2015-02-05 Created: 2015-02-05 Last updated: 2017-06-29
Hubbert, L., Sundbom, P., Loebe, M., Peterzén, B., Granfeldt, H. & Ahn, H. (2014). Acoustic Analysis of a Mechanical Circulatory Support. Artificial Organs, 38(7), 593-598
Open this publication in new window or tab >>Acoustic Analysis of a Mechanical Circulatory Support
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2014 (English)In: Artificial Organs, ISSN 0160-564X, E-ISSN 1525-1594, Vol. 38, no 7, p. 593-598Article in journal (Refereed) Published
Abstract [en]

Mechanical circulatory support technology is continually improving. However, adverse complications do occur with devastating consequences, for example, pump thrombosis that may develop in several parts of the pump system. The aim of this study was to design an experimental clot/thrombosis model to register and analyze acoustic signals from the left ventricular assist device (LVAD) HeartMate II (HMII) (Thoratec Corporation, Inc., Pleasanton, CA, USA) and detect changes in sound signals correlating to clots in the inflow, outflow, and pump housing. Using modern telecom techniques, it was possible to register and analyze the HMII pump-specific acoustic fingerprint in an experimental model of LVAD support using a mock loop. Increase in pump speed significantly (P less than 0.005) changed the acoustic fingerprint at certain frequency (0-23 000 Hz) intervals (regions: R1-3 and peaks: P1,3-4). When the ball valves connected to the tubing were narrowed sequentially by similar to 50% of the inner diameter (to mimic clot in the out-and inflow tubing), the frequency spectrum changed significantly (P less than 0.005) in P1 and P2 and R1 when the outflow tubing was narrowed. This change was not seen to the same extent when the lumen of the ball valve connected to the inflow tube was narrowed by similar to 50%. More significant (P less than 0.005) acoustic changes were detected in P1 and P2 and R1 and R3, with the largest dB figs. in the lower frequency ranges in R1 and P2, when artificial clots and blood clots passed through the pump system. At higher frequencies, a significant change in dB figs. in R3 and P4 was detected when clots passed through the pump system. Acoustic monitoring of pump sounds may become a valuable tool in LVAD surveillance.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2014
Keywords
Mechanical circulatory support; Frequency analysis; Thrombosis
National Category
Cardiac and Cardiovascular Systems
Identifiers
urn:nbn:se:liu:diva-112071 (URN)10.1111/aor.12244 (DOI)000343223400001 ()24372095 (PubMedID)
Available from: 2014-11-14 Created: 2014-11-13 Last updated: 2017-12-05Bibliographically approved
Sundbom, P., Hedayati, E., Peterzén, B., Granfeldt, H., Casimir Ahn, H. & Hübbert, L. (2014). Young Woman With Breast Cancer and Cardiotoxicity With Severe Heart Failure Treated With a HeartMate II (TM) for Nearly 6 Years Before Heart Transplantation. ASAIO journal (1992), 60(6), E3-E4
Open this publication in new window or tab >>Young Woman With Breast Cancer and Cardiotoxicity With Severe Heart Failure Treated With a HeartMate II (TM) for Nearly 6 Years Before Heart Transplantation
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2014 (English)In: ASAIO journal (1992), ISSN 1058-2916, E-ISSN 1538-943X, Vol. 60, no 6, p. E3-E4Article in journal (Refereed) Published
Abstract [en]

Cardiotoxicity is a multifactorial problem, which has emerged with the improvement of cancer therapies and survival. Heart transplantation is relatively contraindicated in patients with breast cancer, until at least 5 years after complete remission. We present a case where a young woman who in 2001, at the age of 31, was diagnosed with breast cancer. She was considered cured, but 4 years later she suffered a relapse. During her second treatment, in 2006, she suffered from severe heart failure. She received a HeartMate II, as a long-term bridge to transplantation and 6 years later she was successfully transplanted. In this case report we discuss the use of mechanical circulatory support in cancer patients with drug-induced heart failure.

Place, publisher, year, edition, pages
Lippincott, Williams andamp; Wilkins, 2014
Keywords
breast cancer; cardiotoxicity; heart failure; mechanical circulatory support; heart transplantation
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-113018 (URN)10.1097/MAT.0000000000000138 (DOI)000345299200001 ()25232773 (PubMedID)
Available from: 2015-01-12 Created: 2015-01-08 Last updated: 2017-12-05
Sundbom, P., Hedayati, E., Peterzén, B., Granfeldt, H., Ahn, H. & Hübbert, L. (2013). Kardiotoxicitet med terminal hjärtsvikt och nästan sex år med Heartmate II i väntan på hjärttransplantation. In: : . Paper presented at Thoraxmötet 2013, 17-18 oktober, Linköping.
Open this publication in new window or tab >>Kardiotoxicitet med terminal hjärtsvikt och nästan sex år med Heartmate II i väntan på hjärttransplantation
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2013 (Swedish)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-104988 (URN)
Conference
Thoraxmötet 2013, 17-18 oktober, Linköping
Available from: 2014-03-05 Created: 2014-03-05 Last updated: 2015-11-09Bibliographically approved
Casimir Ahn, H., Granfeldt, H., Hübbert, L. & Peterzén, B. (2013). Long-term left ventricular support in patients with a mechanical aortic valve. Scandinavian Cardiovascular Journal, 47(4), 236-239
Open this publication in new window or tab >>Long-term left ventricular support in patients with a mechanical aortic valve
2013 (English)In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 47, no 4, p. 236-239Article in journal (Refereed) Published
Abstract [en]

Objectives. The presence of a mechanical prosthesis has been regarded as an increased risk of thromboembolic complications and as a relative contraindication for a left ventricular assist device (LVAD). Five patients in our center had a mechanical aortic valve at the time of device implantation and were studied regarding thromboembolic complications. Design. Five patients operated upon with an LVAD (1 HeartMate I (TM), 4 HeartMate II (TM)) between 2002 and 2011 had a mechanical aortic valve at the time of implantation. The first patient had a patch closure of the aortic valve. In four patients, the prosthesis was left in place. Anticoagulants included aspirin, warfarin, and clopidogrel. Results. The average and accumulated treatment times were 150 and 752 days, respectively. Three of the five patients showed early signs of valve thrombosis on echo with concomitant valve dysfunction. Four patients were transplanted without thromboembolic events during pump treatment. One patient died from a hemorrhagic stroke after 90 days on the LVAD. Conclusions. The strategy of leaving a mechanical heart valve in place at the time of LVAD implantation in five patients led to valvular thrombosis in three but did not provoke embolic events. It increased the complexity of postoperative anticoagulation.

Place, publisher, year, edition, pages
INFORMA HEALTHCARE, TELEPHONE HOUSE, 69-77 PAUL STREET, LONDON EC2A 4LQ, ENGLAND, 2013
Keywords
aortic valve, left ventricular support, mechanical valve
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-96976 (URN)10.3109/14017431.2013.795655 (DOI)000322607700007 ()
Available from: 2013-09-05 Created: 2013-09-02 Last updated: 2017-12-06
Engström, A. E., Granfeldt, H., Seybold-Epting, W., Dahm, M., Cocchieri, R., Driessen, A. H., . . . Henriques, J. P. (2013). Mechanical circulatory support with the Impella 5.0 device for postcardiotomy cardiogenic shock: a three-center experience. Minerva Cardioangiologica: Journal on Cardiovascular Pathophysiology, Clinical Medicine and Therapy, 61(5), 539-546
Open this publication in new window or tab >>Mechanical circulatory support with the Impella 5.0 device for postcardiotomy cardiogenic shock: a three-center experience
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2013 (English)In: Minerva Cardioangiologica: Journal on Cardiovascular Pathophysiology, Clinical Medicine and Therapy, ISSN 0026-4725, E-ISSN 1827-1618, Vol. 61, no 5, p. 539-546Article in journal (Refereed) Published
Abstract [en]

AIM:

Postcardiotomy cardiogenic shock (PCCS) is associated with high mortality rates, despite full conventional treatment. Although the results of treatment with surgically implantable ventricular assist devices have been encouraging, the invasiveness of this treatment limits its applicability. Several less invasive devices have been developed, including the Impella system. The objective of this study was to describe our three-center experience with the Impella 5.0 device in the setting of PCCS.

METHODS:

From January 2004 through December 2010, a total of 46 patients were diagnosed with treatment-refractory PCCS and treated with the Impella 5.0 percutaneous left ventricular assist device at three european heart centers. Baseline and follow-up characteristics were collected retrospectively and entered into a dedicated database.

RESULTS:

Within the study cohort of 46 patients, mean logistic and additive EuroSCORES were 24 ± 19 and 10 ± 4. The majority of patients underwent coronary artery bypass grafting (48%) or combined surgery (33%). Half of all patients had been treated with an intra-aortic balloon pump before 5.0-implantation, 1 patient had been treated with an Impella 2.5 device. All patients were on mechanical ventilation and intravenous inotropes. The Kaplan-Meier estimate of overall 30-day survival was 39.5%.

CONCLUSION:

Thirty-day survival rates for patients with PCCS, refractory to aggressive conventional treatment and treated with the Impella 5.0 device, are comparable to those reported in studies evaluating surgically implantable VADs, whereas the Impella system is much less invasive. Therefore, mechanical circulatory support with the Impella 5.0 device is a suitable treatment modality for patients with severe PCCS.

Place, publisher, year, edition, pages
Edizione Minerva Medica, 2013
Keywords
Shock, cardiogenic, Cardiac surgical procedures, Surgical procedures, operative
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-102786 (URN)000327753600005 ()24096248 (PubMedID)
Note

Funding Agencies|Abiomed Europe GmbH||

Available from: 2014-01-07 Created: 2013-12-26 Last updated: 2017-12-06Bibliographically approved
Hubbert, L., Peterzen, B., Granfeldt, H. & Ahn, H. C. (2012). Acoustic Analysis of a Mechanical Circulatory Support in JOURNAL OF HEART AND LUNG TRANSPLANTATION, vol 31, issue 4, pp S250-S250. In: JOURNAL OF HEART AND LUNG TRANSPLANTATION (pp. S250-S250). Elsevier, 31(4)
Open this publication in new window or tab >>Acoustic Analysis of a Mechanical Circulatory Support in JOURNAL OF HEART AND LUNG TRANSPLANTATION, vol 31, issue 4, pp S250-S250
2012 (English)In: JOURNAL OF HEART AND LUNG TRANSPLANTATION, Elsevier , 2012, Vol. 31, no 4, p. S250-S250Conference paper, Published paper (Refereed)
Abstract [en]

n/a

Place, publisher, year, edition, pages
Elsevier, 2012
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-76943 (URN)000302207900731 ()
Available from: 2012-05-02 Created: 2012-04-27 Last updated: 2012-05-02
Hübbert, L., Jorde, U. P., Peterzén, B., Granfeldt, H., Kornhall, B., Morrison, K. & Ahn, H. C. (2012). Early Results from the SoundMate Study. Acoustic Analysis of a Thromboembolic Event in a Patient Treated with HeartMate II (TM), Mechanical Circulatory Support. Paper presented at 32nd Annual Meeting and Scientific Sessions of the International-Society-for-Heart-and-Lung-Transplantation/Meeting of the ISHLT Academy - Core Competencies in Mechanical Circulatory Support, APR 17-21, 2012, Prague, CZECH REPUBLIC. The Journal of Heart and Lung Transplantation, 31(4 Suppl.), S134-S135
Open this publication in new window or tab >>Early Results from the SoundMate Study. Acoustic Analysis of a Thromboembolic Event in a Patient Treated with HeartMate II (TM), Mechanical Circulatory Support
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2012 (English)In: The Journal of Heart and Lung Transplantation, ISSN 1053-2498, E-ISSN 1557-3117, Vol. 31, no 4 Suppl., p. S134-S135Article in journal, Meeting abstract (Refereed) Published
Place, publisher, year, edition, pages
Elsevier, 2012
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-76942 (URN)10.1016/j.healun.2012.01.388 (DOI)000302207900379 ()
Conference
32nd Annual Meeting and Scientific Sessions of the International-Society-for-Heart-and-Lung-Transplantation/Meeting of the ISHLT Academy - Core Competencies in Mechanical Circulatory Support, APR 17-21, 2012, Prague, CZECH REPUBLIC
Available from: 2012-05-02 Created: 2012-04-27 Last updated: 2017-12-07
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