Exhibit 4.8


 


HEARTBEAM, INC.


 


AMENDMENT NO. 4 TO CONVERTIBLE
PROMISSORY NOTES


 


This Amendment No. 4 to Convertible Promissory
Notes, dated as of September __6_, 2018 (the “Amendment”), is entered into by and among HeartBeam, Inc. (the “Company”)
and certain holders of convertible promissory notes issued by the Company (the “Investors”). Capitalized terms not
defined herein shall have the terms ascribed to them in the Subscription Agreements (as defined below) or the Notes (as defined below).


 


RECITALS


 


A. The
Company and the Investors are parties to certain 2015 Note Subscription Agreements (each, a “Subscription Agreement”
and together, the “Subscription Agreements”), each by and between the Company and the Investor set forth on the signature
page thereto.


 


B. The
Company sold and issued, and the Investors purchased convertible promissory notes in the aggregate principal amount of approximately $2,500,000
(each, a “Note” and together, the “Notes”), pursuant to the Subscription Agreements.


 


C. Pursuant
to Section 6(b) of the Notes, any provision of a Note may be amended, waived or modified upon the written consent of the Company and a
Majority in Interest of Investors.


 


D. The
undersigned Investors represent a Majority in Interest of Investors.


 


E. The
Company and the Investors wish to amend the Notes to adjust the interest rate and maturity date of each of the Notes.


 


AGREEMENT


 


NOW THEREFORE, in consideration of the foregoing,
and the representations, warranties, and conditions set forth below, the parties hereto, intending to be legally bound, hereby agree as
follows:


 


1. Amendment
to Maturity Date. Effective as of the date hereof, the reference to “December 31, 2018,” as the “Maturity Date”
in the introductory paragraph of the Notes and the form of Note attached to the Subscription Agreement shall be amended, restated and
replaced to read “June 30, 2020”.


 


HeartBeam, Inc.


Amendment to Convertible Promissory Notes


 




     


     


    

 


2. Miscellaneous.


 


(a) Amendment.
This Amendment may not be amended, waived, discharged or terminated other than by a written instrument referencing this Amendment and
signed by the Company and the Investors representing a Majority in Interest of Investors.


 


(b) Governing
Law. This Amendment and all actions arising out of or in connection with this Agreement shall be governed by and construed in accordance
with the laws of the State of California, without regard to the conflicts of law provisions of the State of California or of any other
state.


 


(c) Entire
Agreement. This Amendment, the Notes (to the extent not hereby amended) and the Subscription Agreements (as amended), including the
exhibits attached thereto, constitute the full and entire understanding and agreement between the parties for the subjects hereof and
thereof. No party shall be liable or bound to any other party in any manner for the subjects hereof or thereof by any warranties, representations
or covenants except as specifically set forth herein or therein.


 


(d) Severability.
If any provision of this Amendment becomes or is declared by a court of competent jurisdiction to be illegal, unenforceable or void, portions
of such provision, or such provision in its entirety, to the extent necessary, shall be severed from this Amendment, and such court will
replace such illegal, void or unenforceable provision of this Amendment with a valid and enforceable provision that will achieve, to the
extent possible, the same economic, business and other purposes of the illegal, void or unenforceable provision. The balance of this Amendment
shall be enforceable in accordance with its terms.


 


(e) Counterparts.
This Amendment may be executed in one or more counterparts, each of which will be deemed an original, but all of which together will constitute
one and the same agreement. Facsimile copies of signed signature pages will be deemed binding originals.


 


IN WITNESS WHEREOF, this Amendment has been
entered into as of the date first set forth above.


 


	 	COMPANY:
	 	 
	 	HEARTBEAM, INC.
	 	a Delaware corporation


 


	 	By:	/s/ Richard Brounstein
	 	Name:	Richard Brounstein
	 	Title:	CFO


 




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IN WITNESS WHEREOF, this Amendment has been
entered into as of the date first set forth above.


 


	 	INVESTOR:



 


	 	By:	/s/ Branislav Vajdic


 


	 	Print Signatory Name:  	Branislav Vajdic


 


	 	Investor Name:  	N/A
	 	 	(applicable if stockholder is an entity)


 


	 	Title:	 
	 	 	(applicable if stockholder is an entity)


 


	 	INVESTOR:


 


	 	By:	/s/ Wim Elfrink


 


	 	Print Signatory Name:  	Wim Elfrink


 


	 	Investor Name:  	Elfrink Living Trust
	 	 	(applicable if stockholder is an entity)


 


	 	Title:	Trustee
	 	 	(applicable if stockholder is an entity)




 


HeartBeam, Inc.


Amendment to Convertible Promissory Notes


 




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	 	INVESTOR:


 


	 	By:	/s/ Wim Elfrink


 


	 	Print Signatory Name:  	Wim Elfrink


 


	 	Investor Name:  	WPE Ventures Partnership
	 	 	(applicable if stockholder is an entity)


 


	 	Title:	President
	 	 	(applicable if stockholder is an entity)


 


	 	INVESTOR:


 


	 	By:	/s/ William A. Lanfri


 


	 	Print Signatory Name:  	William A. Lanfri


 


	 	Investor Name:  	Pont Holdings, LLC
	 	 	(applicable if stockholder is an entity)


 


	 	Title:	Manager
	 	 	(applicable if stockholder is an entity)


 


	 	INVESTOR:


 


	 	By:	/s/ Stephen P. Mullaney


 


	 	Print Signatory Name:  	Stephen P. Mullaney


 


	 	Investor Name:  	The Mullaney Family Trust
	 	 	(applicable if stockholder is an entity)


 


	 	Title:	Trustee
	 	 	(applicable if stockholder is an entity)


 


 


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